At a time in the far-off future, Earth has become
uninhabitable. A selection of Humanity is placed, deep-
frozen, in a fully automated space station, to await the day
of their return to Earth...
Thousands of years later, DOCTOR WHO arrives. He finds
things going suspiciously wrong, and the station under
attack from the giant WIRRN, deadly creatures who, in
their lust for power, now threaten the future of the whole
Human Race...

ISBN 0 426 11631 3
           DOCTOR WHO
               AND
         THE ARK IN SPACE
 Based on the BBC television serial The Ark in Space by Robert
Holmes by arrangement with the British Broadcasting Corporation.




                    IAN MARTER




                         published by
                   The Paperback Division of
                    W. H. Allen & Co. Ltd
CONTENTS

Prologue: The Intruder
1 The Second Invasion
2 Sarah Vanishes
3 Sabotage!
4 A Fatal Wound
5 The Wirrrn
6 Time Running Out
7 A Tight Squeeze
8 A New Beginning
                 Prologue: The Intruder
       Out among the remotest planets, in faithful orbit through the
Solar System, the great Satellite revolved slowly in the glimmer of a
billion distant suns, reflecting their faint light from its cold and silent
surfaces. All within remained utterly quiet and still, but primed and
ready: ready for the eventual moment of awakening. Deep in its
innermost structure an atomic clock oscillated, waiting for the
moment when it would cause a tiny electric current to flow,
activating circuits which branched throughout the vast Satellite,
bringing it to life once more out in the wilderness of Space.
       Patiently it waited. Then suddenly, after many centuries,
something stirred within it: something alien, that was not part of its
intricate programming. Panels began to slide smoothly open. Faintest
shadows ran over the gleaming walls. The deserted tunnels and
chambers, forming the 'rim', the 'spokes' and the 'hub' of the
enormous wheel, which was the Satellite, began to echo with rustles,
hoarse squeaks and whistlings. Cautiously feeling its way into one of
the spherical control chambers—positioned like gigantic pods along
the 'spoke' sections—there crawled an intruder. It dragged its
massive leathery body along on angular tentacle-legs, which bristled
with sharp hairs and scratched shrilly against the metallic walls.
Swinging its domed head slowly from side to side, it pierced the half-
light with giant, globular eyes. At the end of its long, scorpion tail
there glinted a menacing claw which clattered in the creature's wake.
       As soon as it entered the control chamber, the alien intruder
eagerly scanned the mass of inert instruments which covered the
walls, like exhibits in an abandoned museum. From the domed
ceiling there descended a shining metallic sphere. For an instant the
creature was reflected in its mirror-like surface; information was
flashed to a central computer bank, analysed, and a command relayed
back to the sphere. It glowed brilliantly for a second. The startled
intruder stared defiantly upwards, and at the same instant a fierce
burst of energy sent it clattering against a control console, its
tentacles contracting in agony.
       For a few seconds all was still. Then the creature moved.
Again the sphere glowed, and with a sharp crack hurled it back
across the chamber in a blazing electrical discharge. The creature
cowered, uttering hoarse screams as a stream of brutal shock-waves
pulsed from the sphere, blistering its body with burns. Staring at the
clusters of delicate instruments, its huge eyes useless in the fierce
light, the creature began to flail at the wall panels as if searching
desperately for something. All at once, a section of the panelling slid
open. Fighting the searing bursts of radiation from the sphere, the
creature dragged itself through the opening into a second, similar
chamber. Out of range of the sphere, but now blinded and almost
paralysed, the intruder fumbled among the control consoles lining the
chamber until it somehow located the section it sought.
       With frantic, crippled, movements it ripped open the
instrument panel and pulled out a thick bundle of multi-coloured
cables. Then, arching its segmented tail up over its head, it gripped
the cables in its huge claw and severed them cleanly with a single
slice. At that moment, all through the electronic nerve centres of the
Satellite, certain vital systems were closed down.
       With an unearthly sigh of satisfaction the creature turned
away, and in complete darkness now, crawled back through the first
chamber and out into the labyrinth of tunnels and chambers. Its
mission was almost completed; one final task remained. Slowly and
painfully, but with deadly purpose, it made its way towards the
sleeping humans. The brittle, splintering sound of its movements
died away as panel after panel glided shut behind it. The sphere hung
inert in the darkness.
       When at last the atomic clock signalled the beginning of the
great Awakening, no current flowed. The circuits remained dead, the
systems did not activate. The Satellite continued its eternal orbit, the
Solar Energy Reservoirs absorbing and storing energy from the
sun—though no longer for any purpose.
       Then there came a second invasion...
                            1
                   The Second Invasion
       'Clumsy, ham-fisted idiot,' cried the Doctor, striding out of the
TARDIS into pitch darkness.
       'I'm terribly sorry, Doctor. I was only trying to... trying to open
the door...' stammered Harry Sullivan, just catching the door as it
swung back in his face.
       'Come out of there at once, and don't touch anything else,'
called the Doctor, pausing for a moment in the light streaming
through the door of the TARDIS and staring about him.
       The Doctor was a tall, broad man with a riot of curly brown
hair bubbling out from beneath a stylish felt hat. His generous face
was animated with intense curiosity as his enormous eyes peered into
the semi-darkness. His hands were thrust deep into the bulging
pockets of a voluminous red velvet jacket, and the trailing ends of a
long multi-coloured woollen scarf flapped around his legs as he
moved cautiously away from the TARDIS.
       Surgeon Lieutenant Harry Sullivan RN stood uncertainly in the
doorway, fiddling nervously with his cravat. He was an athletic
young man in his late twenties, with a straight back and a square jaw.
He wore a rowing club blazer and sharply pressed slacks.
       'Oh I say,' he exclaimed, 'we've gone.'
       'Who's gone; Harry?' asked a bright, laughing voice behind
him.
       He turned to face the mischievous smile of Sarah Jane Smith,
who was watching his confusion with evident delight. Sarah was a
slim, level-headed journalist, about the same age as Harry, her trim
figure clad in a trendy denim trouser-suit, her short dark hair tucked
into a saucy woollen hat.
       'Well, I mean this isn't... we aren't where we were when we...'
began Harry, venturing a step or two into the gloom. A few minutes
earlier, when he had entered the old, battered blue Police Telephone
Box, at the Doctor's invitation to have a quick look round, it had been
standing in a corner of the Laboratory at UNIT Headquarters, in
broad daylight. 'I think I've gone mad,' he muttered at last.
        Sarah Jane touched his arm sympathetically. 'I know what you
mean,' she said. 'That's exactly how I felt after my first trip. You'll
find it takes quite a bit of getting used to.'
        The door of the TARDIS swung slowly shut behind them. In
the pitch darkness they could hear the Doctor moving stealthily
about..
        'Where are we, Doctor?' called Sarah casually. A powerful
torch beam snapped on and swept round.
        'Do you know, Sarah, I have no idea,' replied the Doctor after a
pause. Sarah knew precisely what that little pause meant She felt her
way cautiously over to the Doctor's side. The roving torchlight
revealed a large spherical chamber, its walls entirely covered in
instruments, with several flat control consoles, like circular tables,
grouped around it.
        'Just a little trip to the Caucasus, or perhaps once round the
Moon'—Sarah imitated the Doctor in one of his off-hand moods—
'just to prove to Harry that the old Police Box really could travel in...'
        'I didn't expect him to start fiddling with the Helmic
Orientators, Sarah,' interrupted the Doctor sharply. He broke off as
the chamber was dimly illuminated again. Harry had opened the door
of the TARDIS and was staring into it open-mouthed.
        'It's bigger than a Cathedral... on the inside...' he gasped in
amazement. The Doctor strode over and locked the door. Still in a
state of shock, Harry mumbled away in the darkness, 'You know you
could make a fortune out of this thing, Doctor...' But the Doctor was
already pacing about the chamber, sweeping the torch beam over the
curved reflecting walls and closely examining the dense clusters of
instruments.
        Grotesque shadows flapped around them. Sarah shivered. It
was bitterly cold, and the air suddenly seemed terribly thin. It was
quite an effort to breathe. Something loomed up against her. She
jumped. It was Harry.
        'Sorry, Miss Smith,' he mumbled, loosening his cravat, 'but I'm
a bit disorientated...'
         'Not much oxygen,' remarked the Doctor from the shadows.
'Still,' he added cheerfully, 'nothing to worry about.'
         Sarah turned to Harry. 'So suffocation is nothing to worry
about,' she whispered sarcastically.
         'Oh, we can survive for quite a time yet,' boomed the Doctor,
suddenly right beside them. He was concentrating on spinning a yoyo
effortlessly up and down its string in the torchlight.
         Harry decided it was time to speak up. 'Well, I've got quite a
few patients to see at four o'clock;' he tried to affect a casual air, 'so if
you don't mind, Doctor, I'd like to be getting...'
         'A simple gravity reading, Harry,' grinned the Doctor, putting
away the yoyo. 'It would appear that we are inside some kind of
artificial satellite. Now isn't that fascinating.'
         'Doctor, it's dark, it's cold and it's getting very airless,' Sarah
protested loudly. But the Doctor had left them again, and was busily
examining a section of wall panelling away on the far side of the
chamber. He seemed quite oblivious of their discomfort.
         Suddenly they were bathed in a harsh, unwelcoming white
light.
         'There we are,' cried the Doctor, turning. away from the control
panel and surveying the scene with childlike delight, taking in every
detail of their surroundings. He seized the ends of his long scarf and
spun them like propellers. 'Fascinating,' he murmured, 'fascinating.'
In his resonant voice,. excitement, understanding and wonder were
mingled as he crept respectfully round the chamber. For a moment,
his companions' discomfort gave way to amazement.
         'What's it all for?' gasped Harry. He shielded his eyes from the
glare and peered at the coded switches, dials, lights and buttons
covering the circular wall. Despite his anxiety to return to UNIT
Headquarters where he was Chief Medical Officer, he yielded to an
unfortunate curiosity that had already got him into trouble in the
TARDIS. He tinkered with one or two micro-switches on a nearby
console.
         At the same moment, an invisible panel in the wall slid open
directly in front of Sarah.
       'Doctor,' she cried, 'look at this.' But the Doctor was deeply
engrossed in examining the bright metallic sphere which was
suspended from the centre of the domed ceiling.
       'Of terrestrial design certainly,' he muttered, 'but I can't quite
place the period.'
       'Well, none of it seems to be working now,' gasped Harry,
leaning weakly against the control console in an effort to ease the
increasing pain in his chest.
       Sarah looked round at her two heedless companions. She knew
that once the Doctor became involved in something, it was quite
impossible to distract him. Besides, she had a habit of striking out on
her own in search of a good front-page story. She shrugged at their
indifference, and suddenly oblivious of how difficult it was
becoming to breathe, stepped lightly through the opening in front of
her.
       She found herself in a similar, slightly smaller chamber, which
was dominated by a low, couch-like construction supported on a
single slender pillar in the centre of the floor. She recognised the
stream-lined cabinets and tape-reels of computer memory banks set
into the walls. The upper part of the circular wall was patterned with
blank video screens and systems display panels. Sarah leaned against
the couch, her head spinning and her heart pounding. Her eyes tried
to focus on a section of instrument panelling that had been ripped
open, spilling out a cluster of cable ends. She suddenly found herself
fighting for breath. The voices of the Doctor and Harry in the other
chamber gradually receded into the distance...
       '... and judging by that modified version of the Bennet
Oscillator,' the Doctor was saying, 'I would estimate that all this was
put together in the Thirtieth Century.'
       'Oh no,' gasped Harry. 'The Thirtieth what?'
       'You don't agree?' Sarah heard the Doctor inquire indignantly.
Harry muttered something incoherently. Then the Doctor's voice
boomed confidently, 'Oh yes, the late Twenty-ninth or early Thirtieth
I feel sure. For example, Harry, just look at this...'
       Sarah suddenly heard the panel glide shut behind her. She
whirled round. There was no trace of it; she was confronted with a
wall of blank instruments. Sarah stumbled over, her heart. thumping
like a steam engine, and searched for the edges of the panel.
       'There must be a manual control,' she panted. She gulped for
air, scarcely able to fill her lungs. In sudden panic, she pounded and
kicked the panelling. 'Doctor... please... I can't breathe... there's no
air-in here.' She felt herself gripped, as if in a huge vice. Her ears
were ringing and her limbs were numbed. Desperately she clawed at
the wall. 'Doctor... Harry... please help me... pl...' Sarah sank to the
cold floor.
       Harry was leaning against a corner of the TARDIS; despite the
cold he was beginning to sweat with the effort of breathing. 'Look,
Doctor... I'm a straightforward sort of chap,' he gasped, 'are you
telling me that we're now in the middle of the Thirtieth Century?'
       The Doctor seemed totally unaffected by the coldness and the
lack of oxygen. 'Gracious me, no, Harry,' he replied. 'Well beyond
that.'
       'But... where... Where are we?' pleaded Harry, not sure whether
he was dreaming or going insane. The Doctor was kneeling down
and listening intently to the floor through an ancient brass ear
trumpet.
       'Difficult to say,' he murmured, sitting back on his heels and
taking a large bag of jelly-babies from his pocket. 'All this is
obviously quite old,' the Doctor popped a sweet into his mouth,
'several thousand years at least.' He chewed away thoughtfully.
       Suddenly he leaped to his feet. 'Where's Sarah?' he demanded,
advancing on Harry who stared back at him, dumbfounded.
       'Perhaps she went back into the TARDIS,' said Harry.
       'Impossible,' snapped the Doctor. 'I have the key.' He strode
about the chamber, peering closely at the walls through a huge
magnifying glass. 'I have told her time and time again about
wandering off by herself,' he said grimly.
       'Well... there... there must be a door... somewhere,' panted
Harry, his head whirling.
       The Doctor stopped in his tracks and fixed him with a piercing
stare.
       'Not necessarily.'
      Harry glanced longingly at the TARDIS; strange and
incomprehensible though it was, it suddenly seemed very familiar
and safe.
      'You haven't touched anything again, have you, Harry?' the
Doctor demanded accusingly.
      Harry quailed. He was feeling decidedly unwell in the airless
conditions. 'No I... well, yes I... I think I did just press something...'
      'Show me,' commanded the Doctor.
      '... but absolutely nothing happened,' protested Harry. He could
barely stand upright now.
      'Show me exactly what you did, Harry,' coaxed the Doctor
gently.
      Harry tottered over to the control console and stared down at
the maze of instruments. Switches, dials and buttons danced about
before his eyes in the unrelenting white glare. He struggled to
remember. The Doctor's voice seemed to reach him from the other
end of a long long corridor full of slamming doors.
      'Just try to remember, Harry.' Harry's hand wavered
uncertainly; in desperation he pressed a switch.
      Immediately, the panel slid open. Sarah lay just inside the
smaller chamber in a crumpled heap. At once Harry recognised the
bluish pallor around her lips. 'She's cyanosed,' he whispered. 'There's
even less air in there. We must get her out.'
      As they bent down to lift Sarah, the panel glided shut
automatically, trapping them all together. The Doctor searched
feverishly for the panel control circuitry. Harry, now almost
completely overcome, sank down against the wall and feebly tried to
prop Sarah into a sitting position.
      'All my... m... my fault... sorry...' panted Harry.
      The Doctor had discovered the damaged panelling and the
cluster of cable ends. He set to work with magnifier and sonic
screwdriver. 'No, no, Harry, I got us into this,' he muttered, deftly
sorting through the broken connections.
      His movements grew rapidly heavier and clumsier as the lack
of oxygen finally began to take effect. 'This... this is quite
extraordinary, Harry,' he panted. 'Gyroscopic Field Governor
Circuit... Temperature Stabiliser... Ah... Oxygen Valves Servo
Backup Circuits...' Several times the Doctor dropped the sonic
screwdriver and the magnifying glass. Once or twice he glanced
anxiously at Sarah and Harry. They were both unconscious. Sweat
ran into his eyes. His two hearts laboured. His hands felt like rubber.
He forced his mind to concentrate on the delicate operation of sonic-
soldering the tiny, complex connections. He kept thinking of the
faithful TARDIS waiting on the other side of the vacuum panel,
ready to take them all to safety—or to anywhere...
        At last, after what seemed an eternity, valves opened with a
precise clicking. There was a gentle hiss of oxygen all round the
chamber. Soon Harry's eyes opened. He struggled into a sitting
position.
        'Only just in time, Harry,' whispered the Doctor hoarsely from
across the chamber. 'Are you feeling better?'
        'Convalescent,' replied Harry, managing a grin. 'All I need now
is a couple of weeks in Blackpool.'
        They laid the unconscious Sarah gently on the couch
construction, and Harry tried to revive her while the Doctor set about
repairing the remaining circuits.
        'There's a mystery here, Harry,' he muttered, 'Something quite
extraordinary; these cables have been bitten through.'
        'Bitten,' echoed Harry, all but letting Sarah tumble to the floor.
        'Yes,' the Doctor continued quietly, 'and whatever was
responsible clearly possessed a reasoning intelligence.'
        'And very large teeth,' added Harry wryly. Sarah's eyelids
flickered and then opened. 'Sarah's coming round,' he said, smiling
with relief.
        At that moment the panel leading to the other chamber slid
smoothly aside. The Doctor strode triumphantly through. 'Splendid,'
he said. 'All systems go, wouldn't you say?'
        Harry checked Sarah's wavering pulse. 'Now take it easy, old
girl,' he said gently, as she caught at his sleeve in a momentary spasm
of fear. 'You'll be right as ninepence in a few...' The words froze on
his lips as, from the other chamber, there came a deafening crack.
Harry ran across to the panel opening. The Doctor was nowhere to be
seen. Something bright caught his eye. Glancing upwards he saw his
own distorted reflection in the polished sphere suspended from the
ceiling. Before he could step forward he was seized by one ankle and
dragged to the floor. As he fell, something struck his other foot with
the force of a cannonball, tearing off his shoe. He lay quite still, half
under one of the control consoles. The acrid smell of burnt rubber
filled the chamber. For a moment he dared not open his eyes; one
foot was completely numbed, and the other was still held in an iron
grip. He tried to twist himself round and sit upright. His head was at
once thrust roughly back to the floor.
       'Keep down, Harry,' hissed the Doctor in his ear.

      Sarah lay limp on the couch. She felt as if she had floated to
the surface from the bottom of a deep pool. There, in the fresh air,
had been Harry's welcoming smile, but all at once he had
disappeared again and she was alone. She heard the fierce cracking
sounds and Harry's scream of terror. She struggled to get up, but
found herself forced down on to the couch by invisible hands.
Everything about her began to wobble and tiny electric shocks
rippled suddenly through her entire body. She tried to call out, but no
sound would come. Very slowly, and very gently, she was being
pulled apart...

       Outside, in the Main Control Chamber, Harry and the Doctor
crouched silently in the confined space beneath the instrument
console.
       'What happened?' croaked Harry at last, his throat parched with
fear.
       'Just don't move,' whispered the Doctor. He had balanced his
hat on the end of the telescopic probe he always carried, and was
stealthily inching it up into the air above the edge of the console. At
once came the shattering whipcrack from above them; the hat flew
into the shadows beside the TARDIS and lay smouldering. The
Doctor stared at it in anguish. 'I'm afraid we're trapped again, Harry,'
he sighed.
       'But what is it?' gasped Harry.
       'That,' said the Doctor, casting his eyes upward, 'is an
OMDSS.'
       'A what?'
       'An Organic Matter Detector Surveillance System,' answered
the Doctor patiently.
       'A sort of electronic sentry,' suggested Harry, suddenly
catching sight of the shoe that had been blown off his numb foot; it
lay curled. up like a charred kipper. He shuddered.
       'Precisely,' said the Doctor. 'I must confess I was not expecting
this—my repairs next door were a little too thorough.'
       At that moment Harry's mind cleared. He craned his head to
look into the adjacent chamber where they had just left Sarah, but he
could not see the couch construction.
       'Sarah... keep away from the door,' he called. There was no
reply. 'Sarah... can you hear me... Sarah?' But the only sound from
the other chamber was a faint. humming. Harry glanced worriedly at
.the Doctor, but he was totally absorbed in jiggling them metal probe
about in the air. Nothing happened.
       'Just as I thought,' he muttered, 'the system only reacts to
organic matter in motion.'
       'Well that hardly helps us,' said Harry. 'We're organic.'
       'Not under here we're not,' grinned the Doctor mischievously;
his voice booming in the confined space. Harry watched blankly as
the Doctor adjusted the sonic screwdriver and directed it at the joint
between the console support-strut and the floor. The beam of ultra-
high and ultra-low frequency waves soon unsealed the sonic welds...
       '... A little to the right... forward... steady now. One slip, Harry,
and we'll be charcoal.'
       On hands and knees, sheltered by the heavy console which
they carried like a giant umbrella, the Doctor and Harry inched their
way across to the opposite side of the chamber. The silence from the
other chamber was ominous: what if Sarah had blacked out again? Or
worse, what if she suddenly came stumbling through the opening,
unaware of the glittering electronic 'watchdog' in the domed ceiling?
       Gradually they progressed round the chamber, the console
swaying precariously in their combined grip. Even when they paused
for a moment's rest, they had to support the top-heavy 'parasol' by its
single centre leg. Raw-kneed and breathless with effort, Harry
decided that if this really was the Thirtieth Century, then it was an
awfully long way to go just to play the fool.
       At last, the Doctor called a halt. 'There it is, but it's well
beyond reach,' he said, craning upward. Harry was beginning to
resent always being several moves behind.
       'What is?' he asked, exasperated.
       'The Surveillance System Cutout, of course,' replied the
Doctor, deftly fashioning his scarf into a lasso. He flung the loop up
at the switches. There was the now familiar flash and crack, and the
scarf fluttered down in two blazing pieces.
       'Bad luck. Good try though,' whispered Harry admiringly.
       'This is not a game of cricket,' snapped the Doctor.
       'Sorry,' whispered Harry, chastened. 'Mind you, if I had a ball I
could jolly soon reach that switch.' The Doctor silently produced a
worn cricket ball from one of his many pockets. Swallowing his
amazement, Harry took it. He polished it on his lapel. His moment
had come at last.
       The ball, with a good off-spin to it, had scarcely left his hand
than it exploded into a shower of carbon fragments. 'Organic, of
course,' he muttered, crest-fallen.
       The Doctor leaned forward, slipped off Harry's remaining
shoe, and handed it to him. 'You don't need this any more, do you,
Harry?' he said significantly. Harry was becoming more and more
convinced that he was in the company of a madman, with no hope of
rescuing Sarah or of ever getting back to reality. He opened his
mouth to speak. 'No. Good,' interrupted the Doctor. 'Now listen
carefully,' and he quickly outlined a simple plan...
       ... A few moments later, at a prearranged signal from the
Doctor, Harry flung his shoe high over the console under which they
were still hiding. At the same instant, the Doctor leapt up at the
switch; there was a rapid series of cracks, a smell of burning rubber,
and then silence.
       After a long pause, the Doctor's head appeared slowly over the
top of the control desk, followed, after another long pause, by
Harry's. Cautiously they both stood up. 'That foxed you,' said the
Doctor pulling a face at himself in the mirror surface of the OMDSS.
He wandered over to retrieve the remains of his hat and his scarf,
calling brightly, 'It's all right now, Sarah, you can come out.'
       Harry picked up his two melted shoes. 'The Brigadier will
never believe a word of this,' he thought.
       Suddenly the Doctor's voice sounded urgently from the other
chamber. 'Sarah... Sarah, where are you... ?'
       With a shoe in each hand, Harry padded over to the opening.
The Doctor was standing alone beside the couch. All around, the
chamber lights were beginning to flash on the instrument panels, and
a multitude of quiet humming sounds enveloped them. The chamber
seemed almost to be coming alive. The Doctor turned to Harry, his
face filled with anxiety.
       'Sarah's not here,' he said.
                            2
                      Sarah Vanishes
       Sarah tried to scream, but the only sound she heard was a
distant murmuring which grew gradually louder and more distinct. It
was repeating over and over again a hypnotic refrain. 'Welcome,
Sister, welcome to Terra Nova... Welcome, Sister, welcome to Terra
Nova...'
       Finding herself suddenly free of the invisible hands that had
seemed to tear at her body, Sarah struggled feebly to sit up. At once
the mysterious voice spoke firmly but gently. 'No, Sister, do not
move. Do not attempt to leave, the Tranquiller. Remain in contact
with the Biocryonic vibrations.' Too weak to disobey, Sarah lay back
and stared listlessly about her. She was too exhausted even to be
afraid.
       All she could remember was a terrifying sense of suffocation,
then a brief moment of relief with the Doctor and Harry bending over
her, followed by the sounds of a violent struggle and Harry's cry of
distress, and finally the sensation of being slowly dismembered. The
couch on which she was lying seemed familiar, but she did not
remember it being encased in the translucent, glass-like canopy
which now confined her. As she stared at it, the surface of the curved
shield appeared to be in constant motion, just like the surface of a
soap bubble. The harder she stared, so the patterns changed until they
began to resemble huge, eerie shadows cast by something moving
about on the other side of the glass.
       The soothing voice began again, scarcely audible, and for a
moment Sarah imagined that she could hear the Doctor and Harry
talking, and that it was their shadows playing over the canopy. She
tried to call out to them, but still she could make no sound. Panic-
stricken, she attempted to hammer on the glass to attract attention,
but found she could not raise her arms from the couch. She was
trapped.
       As before, the strange voice grew more distinct. It had a
slightly mechanical tone, and echoed around her as if she were inside
a vast cathedral. 'Sister, the principal phase of your Biocryogenic
Processing is about to commence...'... Cryogenic... cryogenic... the
word reverberated in Sarah's mind. She tried to remember; what was
it? Something to do with freezing... yes, freezing... the theory of
tissue preservation for long periods of time... from the Greek word
for frost... She fought hard to keep hold of her train of thought, but
the trance-like voice went inexorably on—'... If you have any
message that you wish to be conveyed to the members of your
Community, you may record it at the end of this announcement.
Please preface your message with your Personal and your
Community Identification Codes...'
       During the pause which followed, the space around Sarah
began to fill with a white vapour that chilled her body. As it grew
thicker and thicker, she felt her skin tightening and growing numb.
The more she gasped with the coldness, the more the freezing vapour
pierced her lungs. As it filled the capsule in which she was trapped, it
seemed to solidify into a gelatinous mass; Sarah lay like a fish
imprisoned in ice. She felt her blood running literally cold, her veins
and arteries contracted around the chilling fluid as it coursed through
her. She felt her heartbeat slowing and labouring. Her body appeared
to merge into the cold jelly surrounding her. Shattering ripples burst
through her as the substance began to vibrate at an ever increasing
frequency. Within a few minutes, Sarah had lost all sense of her
physical reality. She was aware only of her failing consciousness,
and of the sound of a new voice, the quiet, authoritative voice of an
elderly woman.
       'Greetings, Sister Volunteer. On behalf of the World
Executive, I, the High Minister, salute you who are about to make the
supreme sacrifice. In a moment you will pass beyond life. Lest there
should remain any doubt in your mind or fear in your heart,
remember; you take with you not only your own, but all our pasts.
We, who remain to perish here, will live again in you. You are our
only future... our only hope...' The voice finally faded into silence,
and with it, Sarah lost consciousness. After a while, the white
substance thinned and finally vapourised and disappeared. When it
cleared, the couch was empty.

       'Harry, I am an idiot.' The Doctor and Harry were bending
anxiously over the couch on which, five minutes earlier, they had
placed the semi-conscious Sarah. While they had been fighting their
duel with the OMDSS in the other chamber, Sarah had apparently
disappeared into thin air. Having satisfied himself that there were no
more concealed panels through which she could have gone, the
Doctor had removed a part of the upholstered section of the couch,
and exposed a honeycomb of small cells, each about the size and
shape of the reflector in a bicycle lamp. The cells were inter-
connected with fine coppery wiring embedded in a perspex frame.
       Harry was relieved that, just for once, he was not to blame for
what had happened.
       'Fortunately it's only an internal relay,' said the Doctor,
glancing up at one of the instrument displays set into the circular
wall.
       'A what?' Harry looked from the couch to the instrument panel
and back to the Doctor.
       'A short-range Matter Transmitter,' snapped the Doctor,
striding back into the main chamber. Harry padded after him, still
clutching the remains of his shoes.
       'What on earth does that mean?'
       'It means,' called the Doctor, stepping through another panel in
the main chamber which opened automatically as he approached it,
'that Sarah can't be very far away. Do come along, Harry.'
       Slithering on the smooth metal flooring, Harry followed. As he
entered the long tunnel-like passage leading from the chamber, he
was amazed to see that the Doctor had already reached the other end
and was waiting impatiently for him. All at once, Harry's feet were
swept from under him, and he found himself sitting on a moving
track running down the centre of the tunnel. It carried him smoothly
with a faint hum to the far end. Just as he scrambled to his feet,
convinced that he was about to crash headlong into the bulkhead at
the end of the tunnel, the track slowed and stopped. Harry had no
time to express his astonishment; the Doctor was already
disappearing through a panel he had opened in the bulkhead wall.
       They found themselves at a 'T' junction, where the tunnel
joined at right angles with a spacious gallery which curved away out
of sight in both directions. The Doctor motioned Harry to stay where
he was, then advanced cautiously into the middle of the intersection.
All the surfaces of the gallery were made of the same highly
reflective metal, and a harsh white light flooded everywhere from a
concealed source. Along the outer wall of the gallery, at intervals of
a few metres, were set large ovoid window panels of tinted glass,
through which a brilliantly clear night sky blazed. It was clearer than
Harry had ever seen it before.
       'I say,' he breathed. 'It's beautiful...' The words faded from his
lips as he realised with a start that the billions of stars were moving
slowly but unmistakably across the panels. He felt momentarily
unsteady, as if a ship's deck were heaving beneath his feet. 'We're...
we're moving,' he said, his eyes wide.
       'This is no time for star-gazing, Harry,' called the Doctor,
setting off briskly to the left. When Harry finally tore his eyes away
from the splendid panorama through the observation panels, the
Doctor had already disappeared round the curve.
       'This must be the size of a running track,' panted Harry, as he
hurried to catch up.
       'Naturally.' The Doctor grinned over his shoulder. 'We are now
in the Cincture Structure.'
       'The what?' Harry skidded in his stockinged feet.
       'The outer wheel,' called the Doctor. 'We appear to be inside an
old Centrifugal Gravity Satellite, shaped rather like a doughnut with
an éclair stuck through the middle and connected to it by several
chocolate fingers.'
       Harry rather resented the Doctor's oversimplified explanation.
'I suppose we are now walking round inside a doughnut,' he
remarked. But his sarcasm was lost on the Doctor.
       'Exactly,' he said. 'Of course it has been converted to a more
sophisticated Electrostatic Field Gravity System, but it still revolves
on its axis because there's simply nothing to stop it.'
       They were approaching another bulkhead. In the centre of its
sealed panel there was a stencilled notice in green and maroon
striped computer lettering:

                     TECHNOP
             FIRST           PERSONNEL ONLY
                     MEDTECH

       Just before they reached it, the Doctor darted suddenly through
yet another automatic panel which opened silently in the inner side
wall. He re-emerged immediately, much to Harry's relief. 'Well,
Sarah's not in there,' he said, striding on towards the bulkhead
barring their way. All at once a disembodied metallic voice barked at
them: 'STERILE AREA'.
       The Doctor paused in his tracks, and Harry leaped backwards
as if he had trodden on a nail. All these hidden, automatic panels,
electronic guards, hidden voices and moving floors made him feel as
if he were trapped in a crazy maze at a funfair. However the Doctor
seemed perfectly at home; he had rested his head against a small
copper plate at the side of the bulkhead panel, and seemed to be
meditating. After a few seconds the panel opened.
       'How did you do that?' exclaimed Harry.
       'Alpha waves and things,' the Doctor tapped his head. 'It's
surprising what one can do with a little thought.' He ushered Harry
through the opening.
       'Do you think we should?' asked Harry anxiously,
remembering the curt, nightmarish announcement they had just
heard.
       'Probably not,' grinned the Doctor mischievously, turning to
close the panel behind them.
       At that moment, Harry caught a glimpse of something moving,
just at the point where the gallery ahead curved out of sight.
Something appeared to slither quickly across the floor; he had a
momentary impression of a pulsating cluster of fluorescent bubbles,
and of a faint crackling sound like toffee paper. He froze, speechless
with fright, then grabbed the Doctor's sleeve.
       'Doctor, there's something there,' he whispered, pointing to the
spot. The gallery stretched in a graceful arc, the bright stars gliding
slowly across the observation panels.
       The Doctor looked doubtful. 'Trick of the light, Harry,' he
shrugged.
       'No. I saw something moving,' Harry insisted. He crept
forward a few metres. Suddenly he found his stockinged feet glued
firmly to the floor. He gave a startled yelp, and looked slowly down.
He had stepped on a faint, silvery trail of sticky substance—about
thirty centimetres wide—which traversed the gallery from wall to
wall.
       The Doctor knelt down and examined it closely through his
magnifier. 'Fascinating,' he exclaimed at last. 'Just like the track left
by a gastropod mollusc.'
       Harry stared incredulously at him. 'A snail? That size?' He tore
his feet free from the adhesive trail, leaving wisps of wool stuck fast
to the floor. 'That's impossible, Doctor, and anyway, how could it
have got through there?' Harry pointed to the fine-mesh grille set into
the base of the inner wall, into which the trail disappeared. The
Doctor grunted, tracing the silver track across the gallery and up the
outer wall where it disappeared into a similar grille set between two
of the window panels.
       'A multi-nucleate organism perhaps?' he said.
       Harry's confidence began to return. Here was a subject about
which he felt he knew something. 'But surely, Doctor, such an
organism would not be capable of moving that fast...'
       'Come on,' interrupted the Doctor, 'let's find Sarah first. Ah,
this looks promising.' He strode towards a panel in the inner wall, a
few metres along from the grating. As before, he knelt down and
rested his forehead against the small plate set into the wall, frowning
in profound concentration. Nothing happened; the panel remained
shut. The Doctor stood up for amoment and mopped his brow, then
he leaned forward and tried again, his face creased with effort. After
a long pause, Harry jumped as the panel suddenly zipped open.. Even
the Doctor looked a trifle surprised.
       'That must have been some idea you had.' Harry grinned
admiringly.
       The Doctor shrugged. 'Oh, just a little notion for a new
opening gambit in four-dimensional chess.'
       They stepped into a small cubicle resembling a lift. The panel
closed behind them. They stood awkwardly nose to nose.
       'Well, she's obviously not in here...' began Harry wearily. A
rapid series of extremely uncomfortable sensations pulsed through,
his entire body, as if it were expanding to the size of an elephant and
at once contracting to that of a flea, and then expanding again in
quick succession.
       'Decontamination Chamber,' said the Doctor, quite unaffected.
Harry felt as if he were being shaken to a jelly. 'Ultra high and low
frequency oscillations,' the Doctor added casually, 'confuses the
microbes—much more efficient than your old-fashioned antibiotics.'
       When the vibrations stopped, a second panel opened in the
opposite wall, revealing a long straight tunnel bathed in soft greenish
light. Another moving track carried them smoothly and swiftly along
it.
       'This must lead to the central hub-structure,' said the Doctor
eagerly. He continued to mutter to himself, gesturing from side to
side at the fluorescent systems-displays which lit up one by one as
they passed. Harry struggled to keep upright as they glided along, his
head whirling like a stone at the end of a long string. Without
warning, the Doctor put out his hand towards the wall of the tunnel
and the conveyor stopped moving. Harry all but fell flat on his face.
       The Doctor was staring at a large, complex display marked:

             NEURO ADVANCE/RETARD PULSORS

      The display consisted of a mass of regularly arranged, tiny
neon lamps with illuminated connecting circuits. Some were pulsing
weakly, others were inactive, and a few were flashing strongly with a
long slow rhythm. The Doctor's eyes widened: 'Harry, do you realise
what all this is?' he said excitedly, removing his hand from the wall
and setting the floor in motion again with a jerk. 'It's a complete
Cryogenic Suspension System inside a converted Navigation
Satellite.' But Harry scarcely heard; he was still clutching his aching
head. The Doctor stopped the conveyor every few metres to examine
the complex displays of coded circuitry which lit up as if by magic.
He grew more and more animated. 'There's not the slightest doubt...'
he cried... 'Fascinating...' Harry could only manage a groan of pain
and confusion.
       'When they reached the far end of the softly-lit tunnel, they
were confronted with yet another panel. It bore a stencilled
identification:

                                 TECHNOP
 ACCESS CHAMBER: FIRST                   PERSONNEL ONLY
                                 MEDTECH

       The Doctor immediately took out his ear trumpet and placed
the horn against the bulkhead frame. He listened intently for a while.
'We're in luck, Harry,' he said at last. 'The release-lag relay has
operated—we can go in.' Harry was not at all sure that was a good
thing, but he was in no condition to protest.
       They entered a 'fat' crescent-shaped chamber, much larger than
those they had already seen. One entire half of the straighter wall was
patterned with a multi-coloured chequer-board of tiny coded panels.
On the other side of a large access panel in the centre of the wall,
there was a series of semi-circular observation ports emitting a faint,
bluish light. Opposite, set into the inner wall of the crescent, was a
couch, identical to the one in the Control Chamber from which Sarah
had disappeared, except that this one was covered by a curved
transparent shield. Control consoles, elegant flat structures supported
on single struts, were grouped all round the chamber. The subdued
lighting gave the chamber a solemn, church-like atmosphere.
       'We're getting warm, Harry,' said the Doctor, striding over to
examine first the couch, then the control consoles.
       Harry shivered; on the contrary, it seemed to him to be
decidedly chillier in here. He tottered over and leaned against the
chequered section of wall, still feeling the effects of the
Decontamination Chamber. He stared across at the empty couch.
'Well, she certainly isn't here,' he said.
       Totally absorbed, the Doctor darted over to peer through the
observation ports: 'Balaenoptera musculus,' he exclaimed, his eyes
brightening.
       'The Blue Whale,' Harry translated mechanically. Then he
froze.
       Something had touched him on the shoulder from behind, and
pushed him firmly away from the wall. He staggered forward, mute
with terror, and collapsed in a heap. The Doctor glanced round. His
enormous eyes opened wide. He leaped over the spreadeagled Harry
with a cry. Harry dared not turn his head.
       'Just look at this,' the Doctor shouted delightedly. One of the
little coded panels had sprung open, revealing itself to be a long
narrow drawer, packed with what looked like miniature tape
cassettes. The Doctor quickly opened several others. 'Everything they
considered worth preserving,' said the Doctor slowly. 'Architecture...
Electronics... Agriculture... Music... the sum of human knowledge...
here.'
       'Who... I mean what for...?' muttered Harry, hauling himself to
his feet.
       'Posterity?' shrugged the Doctor, wandering thoughtfully round
the chamber. He suddenly stopped directly in front of Harry. 'What's
missing, Harry?' he demanded. Harry was about to point out that for
one thing Sarah was missing, when the Doctor seized him by the arm
and marched him over to the observation ports. Harry screwed up his
eyes and peered into one marked ANIMAL AND BOTANIC.
       Dim shapes hung in the cobalt gloom. For a moment Harry
thought he glimpsed an elephant—or rather two elephants—and
something that looked very like a palm tree. He backed away,
rubbing his eyes. 'Please, Doctor,' he implored, 'the straight-forward
human mind isn't capable of...'
       'Exactly,' the Doctor smiled. 'Man—The Human Species is
quite conspicuously absent.' He sat down and gestured around him.
'If we assume that some catastrophe occurred on Earth and that,
before the end, this Satellite was converted to function as a
Cryogenic Preservation System...'
       'A sort of Noah's Ark,' said Harry. The Doctor nodded...
       '... The missing element is Man himself. What has happened to
the Human Species, Harry?' The Doctor fixed Harry with a
penetrating stare and leaned back on the instrument panel, his elbow
depressing a series of touch-buttons...
       From behind the reflecting surfaces of the chamber walls came
the subdued clatter of relays operating. With a sonorous humming, a
section of the wall slid slowly aside. The space beyond was filled
with a faint, iridescent glow quite unlike anything Harry had ever
seen. A wave of coldness enveloped them, as if a long imprisoned
breath had been released from the phosphorescent depths with an
almost audible sigh. It was as if the chamber beyond were
whispering to itself.
       Awestruck, Harry followed the Doctor over to the opening,
and stood at his shoulder. They were on the threshold of an
immensely tall chamber composed of three semicircular bays
arranged around a broad shaft rising through the centre. At its widest,
the chamber was at least thirty metres across. Alcoved sections, each
containing a covered pallet, were grouped side by side around the
bays. The rows of recessed pallets were ranged in storeys stretching
out of sight into pitch darkness above them, and each storey was
surrounded by a narrow gallery connected to the circular central shaft
by catwalks. The criss-cross of glinting metal tracery reminded Harry
of the framework of an airship stood on end.
       The phosphorescent light filling the chamber came from the
translucent shields protecting the pallets; each shield was moulded to
the contours of the human form. As their eyes became accustomed to
the alien half-light, the Doctor and Harry discerned the outline of a
human body suspended in each alcove. In the cold silence the effect
was like that of entering a huge mausoleum.
       'What a pl...' began Harry. His voice rang and reverberated
round the chamber. He went on in an abashed whisper, 'What a place
for a Mortuary. Look, Doctor, there must be hundreds of them.'
       The Doctor advanced a few paces, craning upwards with an air
of respect. 'This is no Mortuary, Harry. Quite the reverse. It's an old
principle, but I've never seen it applied on this scale before.'
       As they began to walk slowly round, staring up at the
seemingly endless array of bodies, Harry tried to conceal his unease
beneath an air of professional detachment. 'When you've seen one
corpse you've seen them all,' he shrugged.
       The Doctor wandered into the shadows of the next bay,
peering through the shields as if examining exhibits in a museum.
'These people are not dead, Harry, they're asleep.' He continued to
speak, his voice rising and echoing majestically around the vast
vaults. '... Homo Sapiens... what an indomitable species... it is only a
few million years since it crawled up out of the sea and learned to
walk... a puny defenceless biped... it has survived flood, plague,
famine, war... and now here it is out among the stars... awaiting a
new life. That's something for you to be proud of, Harry... Harry!
What do you think you are doing?'
       The Doctor had made a complete circuit of the chamber, and
come upon Harry examining the pupils of an occupant whose shield
he had managed to prise open. Harry pointed to the slim, fair-haired
young man lying there inert with open, staring eyes. He was dressed
in a simple white uniform with green identification flashes. There
was no colour in his face, and his skin was waxen and cold.
       'There you are, Doctor,' said Harry triumphantly, 'not a flicker
of life.'
       'Suspended Animation,' retorted the Doctor, pushing Harry
aside and quickly closing the shield.
       'But there are no metabolic functions at all,' protested Harry.
'Even in the deepest coma you will, find that the...'
       'Total Cryogenic Suspension, Harry,' the Doctor interrupted
impatiently. 'You can't survive ten thousand years in a coma.'
       Harry stared at the shrouded figure. 'Ten... thousand years?' he
said. 'That's impossible...'
       'Oh, ten thousand... fifty thousand—the time is immaterial.
Provided, of course, that no one interferes with the systems,' the
Doctor added pointedly. Harry glanced wildly about at the ranks of
inert human bodies, his mind reeling. The Doctor spoke in an almost
reverent hush. 'The future of the entire human race in one chamber.'
        Carefully he checked that the pallet Harry had opened was
firmly closed and sealed again. 'Come along, Harry,' he said. 'We
must find Sarah, and then take our leave. We're intruders here.'
        Anxious not to irritate the Doctor any further, Harry resisted
the flood of questions rising in his mind and followed him towards
the entrance. As he turned for a last look at. the awesome spectacle,
Harry's heart missed a beat; his shoeless feet were suddenly held in a
fierce grip that all but toppled him over.
        'Doctor, look,' he breathed. He was stuck fast to another silvery
trail snaking across the floor of the chamber. It was identical to the
one they had found earlier. It disappeared into a grille at the base of
the central shaft.
        The Doctor dropped to his knees and began tracing the sticky
trail as it wound away into the shadows.
        'Perhaps it's some kind of mould,' suggested Harry.
        'But you said you saw something moving before,' the Doctor
reminded him. Harry shivered and looked uneasily around. He
remembered the Doctor's reference to giant snails.
        Something caught his eye in one of the pallets in the opposite
bay. It looked different from the others. The Doctor was busy trying
to scrape off a sliver of the tacky substance with the probe. On tip-
toe, his socks still sticking slightly to the floor, Harry cautiously
approached the pallet. As he peered into it, he thought he detected a
swirling, vaporous movement. Glancing round to make sure the
Doctor was still occupied, Harry eased open the magnetic shield...
        There, her skin like chalk and her body cold and rigid, lay
Sarah Jane Smith. For a moment Harry was speechless, riveted by
Sarah's fixed, expressionless gaze. Then he gasped 'Sarah...'
        The Doctor was at his side in an instant, ready to reprove him
for his meddlesome ways. When he saw Sarah his huge eyes nearly
popped out of his head. Very quietly he said, 'There's nothing we can
do for her, Harry.' Instinctively Harry moved forward to lift Sarah
out of the pallet. The Doctor firmly gripped him by the arm. 'We're
too late,' he whispered. 'She's become part of the process. We'll only
harm her if we interfere now.'
        Harry stared at him in horror. 'There must be something I can
do,' he cried.
        Shaking his head firmly, the Doctor started to close the
magnetic shroud. 'Sarah will remain like that for a thousand years at
least.'
        'Not if I can help it,' said Harry defiantly. Earlier he had
noticed the outlines of coded inspection panels set into the central
shaft. He gestured hope-fully towards them. 'Couldn't we break into
the works?' he pleaded. 'Reverse the process or something?' But
again the Doctor shook his head resolutely.
        On a sudden impulse, Harry darted across to the shaft and
began clawing frantically at the smooth, sealed edges of the panels.
Before the Doctor could restrain him, he had sprung open a hatch the
size of a door. He found himself staring into a dark cubicle, and for a
split second he caught a glimpse of an enormous locust-like figure
with gigantic eyes, looming over him like an insect Buddha. Then, as
he sprang backwards with a scream of terror, something toppled
slowly past him with a sickening crunching sound. There was a
clatter of brittle tentacles and antennae which fractured and scattered
a gelatinous cobweb substance all over him.
                              3
                           Sabotage!
       Harry stood with his back pressed against the curved wall of
the shaft. He was trembling, and his face was beaded with sweat. He
stared at the enormous 'insect' which lay crumbling at his feet. The
surface of its segmented body was a glossy indigo colour; here and
there were patches of twisted and blackened tissue, like scorched
plastic.. The six tentacular legs bristled with razor-sharp 'hairs'. The
creature's octopus head contained a huge globular eye on each side,
and each eye was composed of thousands of cells in which Harry
saw himself reflected over and over again. The. creature was fully
three metres long from the top of its domed head to the tip of the
fearsome pincer in which its tail terminated.
       At last Harry managed to speak. 'At least it's dead,' he gasped.
       The Doctor calmly picked up a shattered length of tentacle
which powdered and crumbled in his fingers. 'Practically
mummified,' he nodded.
       'Just look at the size of its brain pan,' said Harry, his fear
gradually giving way to fascination.
       'Clearly a creature of considerable intelligence,' murmured the
Doctor, taking out his magnifying glass and probe. He knelt down
beside the massive corpse.
       'But what is it?' Harry asked, amazed at the Doctor's apparently
fearless curiosity. The Doctor always liked to have a ready answer
for his insatiably inquisitive human companions, but this was one
occasion when he found himself rather at a loss. He did not answer,
but became totally absorbed in an anatomical investigation.
       Harry remained with his back firmly against the shaft, afraid to
move. He looked across at Sarah. She seemed to stare straight back
at him, her face an impassive mask. Harry imagined the open eyes of
all the other humans 'sleeping' in the vast chamber, staring sightlessly
at their own reflections in the polished surfaces, for perhaps
thousands of years the Doctor had said, their bodies without
heartbeat or consciousness, yet alive.
        Suddenly he felt a prickling sensation at the back of his neck.
In one of the pallets the phosphorescent glow seethed to have
intensified. It grew rapidly brighter until he could hardly bear to look
at it, and the silhouette of the occupant appeared to undulate with the
same rhythm as an eerie wobbling hum that filled the chamber and
made Harry cover his ears. The glare and the vibrations
overwhelmed him for a moment. When he came to, he saw the
Doctor standing motionless in front of the pallet which was now
quiet again. The shield was open. Harry moved cautiously round the
central shaft to avoid the huge crumbling corpse, and padded across
the chamber to join the Doctor.
        The pallet was occupied by a dark-haired woman in her
thirties, wearing the same simple white uniform with green flashes as
the young man Harry had examined earlier. But the young woman's
skin was glowing with healthy colour, and Harry noticed that her
pupils were dilating and contracting. She lay with her arms at their
sides, palms outward. In her wrist, Harry's practised eye caught the
beat of a regular pulse.
        Suddenly, her slim body arched in a spasm of pain; then it
relaxed with a gasping intake of breath. She lay panting for a few
moments, her head rolling from side to side. Then her eyes focussed
on the Doctor. A shadow of incomprehension passed across her face.
Slowly she brought her hands together and stared at them. Then she
looked up again at the Doctor, her fingers making urgent grasping
movements.
        'Please do not be alarmed,' the Doctor said gently. 'We are
friends.'
        'She wants us to help her up,' said Harry, hurrying forward.
        'No, Harry. I think this is what she needs.' The Doctor leaned
across and took a small transparent container from a holder fitted to
the inside of the pallet cover. Visible inside the container were
several coloured spheres, like billiard balls, and a gleaming
instrument resembling a spray gun.
       'I shouldn't have opened the shield,' muttered the Doctor,
watching intently as the woman eagerly took out the spray gun, and
carefully fitted one of the small spherical objects into the base of the
handle. She then pressed the star-shaped nozzle against her forehead
and operated a button. There was a brief high-pitched whirr. The
woman's body convulsed and then went limp. After a few moments,
she rose gracefully from the pallet and stood motionless, fixing the
Doctor and Harry with a piercing stare. She was fully two metres tall,
and even the Doctor seemed a little disconcerted by her detached,
authoritative air. She betrayed no emotion at her awakening.
       'Explain your presence here,' she suddenly ordered in a
toneless, clinical voice. She seemed neither surprised nor afraid.
       'Well, there's very little to explain,' began the Doctor amiably.
'We are travellers in space and time like yourself.'
       The woman walked slowly round them. 'That is not adequate,'
she retorted.
       Harry felt extremely uncomfortable under her cold, relentless
stare. 'My name's Sullivan... Surgeon Lieutenant Harry Sullivan...
and this... this is the Doctor,' he mumbled.
       The woman's eyes widened. 'You claim to be Medtechs?' The
note of incredulity in her voice suddenly made her seem a little more
human.
       'Oh, my Doctorate is purely honorary,' said the Doctor with a
conciliatory smile, 'and Harry here is...'
       The woman raised her hand imperiously for silence. 'My name
is Vira. I am First Medtech,' she announced.
       'How very fortunate,' said the Doctor. 'We have a dear young
friend over there who needs your help desperately.' He pointed across
the chamber to where Sarah lay.
       For a moment, Vira stared at the Doctor, evidently on her
guard. Then she walked gracefully across to Sarah's pallet. She
looked at Sarah without emotion. 'The female is an intruder, like
yourselves,' she said icily. Vira turned abruptly away, as if losing all
interest in them. 'She was not among the Chosen,' she said, looking
round at the inert and shadowy forms surrounding them. She
appeared to be listening, waiting—her eyes alert and shining.
       'Well, she's among the Chosen now, isn't she?' blurted out
Harry. Vira turned a withering, blank stare upon him. Harry retreated
a step and bit his lip, regretting his sarcasm.
       The Doctor intervened gently. 'Is there any method of
reversing the Cryogenic function at this stage?'
       'It would be dangerous,' Vira replied distantly. 'Is the female of
value?'
       This was too much for Harry. 'What kind of question is that?'
he exploded, wincing as the Doctor stood firmly on his stockinged
toes.
       'She is of great value to us,' the Doctor said quietly.
       Vira hesitated a moment, then passed her hand over a section
of the pallet frame, activating a small fluorescent systems display.
'Neural activity is rapidly receding,' she declared. 'I will discharge a
monod block.' Vira took out the instruments from the pallet kit, and
repeated the procedure she had performed upon herself earlier. She
pressed the probe against Sarah's temple and triggered the charge.
'The female will revive soon, or die,' she said flatly, replacing the
equipment in the holder. 'At this stage, the action of anti-protonic is
not predictable.'
       Vira turned. On the far side of the chamber, the pallet next to
her own was beginning to glow and to emit the same pulsing hum
which had heralded her own awakening. There was a sudden yielding
in her face. 'Commander,' she whispered, crossing swiftly into the
vibrating glare. 'This is our Prime Unit—Noah.'
       Harry shielded his eyes, and turned to the Doctor.
       'As in Noah's Ark, eh?' he said.
       'Your colony speech has no meaning,' said Vira. 'We called
him Noah as an amusement.'
       'A joke,' Harry corrected her.
       Vira nodded gravely, her eyes fixed on the incandescent shield
of the pallet. 'There was not much joke in the last days,' she added
quietly.
       The Doctor moved to her side. Like Vira, he seemed
unaffected by the fierce light. 'What happened during. those last days
on Earth?' he asked gently.
       Without taking her eyes from the pallet, Vira replied in
amazement, 'Has your colony no records? Where are you from?'
       'Well, Harry's from Earth, and I...' began the Doctor.
       'That is not possible,' said Vira. 'The solar flares destroyed all
life on the Earth.'
       The Doctor nodded. 'Of course, solar flares.'
       Vira opened the shield, now that the radiation had subsided,
and checked the pallet systems-display. 'We calculated that it would
be ten thousand years before the biosphere became viable again,' she
said.
       'At the very least,' agreed the Doctor. 'But I think you have
overslept by several thousand years. When we arrived, we found a
massive systems failure. Your alarm clock failed to work.'
       Vira shook her head. 'The systems have a negative fault
capacity,' she replied sharply.
       The Doctor took her firmly by the arm. 'Possibly,' he said. 'But
at some time you have had other visitors besides ourselves.' He led
Vira across the chamber into the bay beyond the central shaft, where
the monstrous corpse of the locust-like creature lay in the shadows.
Vira showed no fear, only surprise. The Doctor watched her reaction
closely. 'A truant from your Animal and Botanic Section perhaps?' he
suggested.
       'What is it?' Vira demanded suspiciously.
       'I don't know yet,' said the Doctor, peering into one of the
creature's great yellow eyes. 'But it had some purpose in coming
here...'
       'What purpose?' said Vira, suddenly tense, her eyes roaming
over the ranks of softly glowing pallets stretched all around and
above them.
       Before the Doctor could reply, she turned with a gasp and sped
across the chamber to Noah's pallet. The quiet, rhythmic pulse of
light and sound had become irregular and staccato. 'There is a fault in
the Bionosphere,' she cried in disbelief. She wrung her hands in
desperation. Harry was amazed at her sudden helplessness.
      The Doctor swiftly ran his eye over the systems-display. 'There
is an optimum overload in the central power supply,' he said. 'We
must prevent a cascade tripout.'
      Vira gestured to the other pallets in the bay. 'But we have no
Technops, Doctor,' she cried. 'The Programme was planned so that
First Technops and First Medtechs would undergo simultaneous
Revivification.' Again she stared suspiciously at them. 'There has
been interference,' she added threateningly.
      The Doctor strode towards the Access Chamber. 'I think I can
help you,' he said. 'Harry, you keep an eye on Sarah while I'm gone.'
Before Vira could protest he ran out of the chamber.

      Meanwhile, deep in the Infrastructure of the Satellite, far down
inside the central hub of the great wheel where, little by little over
the centuries, energy from the pale and distant Sun had been
focussed and stored in huge reservoirs, a voracious alien life-form
had established its lair. The surfaces of many of the spherical
reservoirs were covered in a glistening, bubbling substance which
pulsated in the dull amber glow of the chamber. Here and there,
along the conduits connecting one reservoir to another, slid clusters
of viscous matter which stretched out and then gathered again into
globules with a dry crackling sound.
      As it spread slowly over the surface. of the reservoirs, the
substance became denser, more opaque and brittle. Occasionally the
crackling globules formed weird, nightmare shapes which swelled
and then burst into long, twisting fronds, hissing and spitting like
snakes. Colossal quantities of the precious energy were absorbed by
the parasite bubbles, so that the vital systems of the Satellite were
increasingly starved of essential power...

       The Doctor swiftly made his way from the Cryogenic-Section
back to the Control Centre where the TARDIS had materialised. As
he hurried along the softly-lit tunnels, he paused briefly to examine
fresh trails of the tacky, silver substance clinging to the floors, walls
and even ceilings. He was rapidly becoming convinced that
something was, at that very moment, engaged in a destructive attack
on the Satellite from within. He crept with the stealth of a predator
stalking its prey—well aware that he himself might be the prey of an
as yet unknown enemy. Reaching the smaller Control Chamber, from
which Sarah had disappeared, the Doctor set to work with the sonic
screwdriver, skilfully rearranging a mass of circuits in an attempt to
provide sufficient power to the Cryogenic systems.
       As he worked, he was aware of an insidious, evil force
infiltrating the innermost parts of the Satellite; a hidden enemy ready
to attack at any moment.

       In the Cryogenic Chamber, Harry waited helplessly at Sarah's
side while Vira concentrated on the life and death struggle of her
own people. She glided from pallet to pallet, checking the systems-
displays, and occasionally administering treatment with an array of
instruments whose function Harry could only guess at.
       'I should have gone myself,' she said at last, returning to
Noah's pallet. 'You are Dawn Timers; your companion has no
knowledge of our Satellite.'
       'Oh, he's an absolute wizard with bits of wire and things,' said
Harry with desperate optimism. 'He'll have it all ticking over in no
time.'
       At that moment the oscillations in Noah's pallet settled into a
steady rhythm again. Vira checked the display, then she turned to
Harry. 'The fault has corrected,' she smiled. 'Noah will soon revive.'
       'Harry?' The Doctor's voice boomed out in. the adjacent Access
Chamber. Harry hurried through. Over the intercom the Doctor asked
whether the power had been restored in the Cryogenic systems. He
said that his lash-up in the Control Centre would not be adequate for
very long, and that he suspected a major fault in the Solar Stacks.
'I'm going down to take a look, Harry,' he boomed.
       'O.K., Doctor,' said Harry apprehensively. 'But don't be too
long...' There came an uncommunicative grunt from the intercom and
then silence. Harry padded back into the Cryogenic Chamber, to find
Vira stretching out her hand in greeting to a tall, slim but powerful
man with short black hair and a trim beard. He was holding out his
hands to her in a simple gesture of recognition.
       'Then it is ended, Vira. We are alive again,' the man said
gently.
       'And together, Commander,' smiled Vira.
       Feeling rather superfluous, Harry wandered across to Sarah's
pallet, and stood watching for a flicker of returning consciousness.
       'Who is this?' Harry swung round at the ice-cold enquiry. Noah
was staring at him with blazing eyes.
       'The name's Sullivan... sir,' Harry began.
       Noah turned to Vira in disbelief. 'A regressive... here?' he
exclaimed.
       'I'm no regressive,' retorted Harry, 'I am a Naval Officer.'
       'Clearly a Regressive—the speech patterns are unmistakable,'
said the Commander in a hollow, detached tone that sent a shiver
through Harry. Vira explained briefly about the Doctor and his
companions. Noah continued to stare at Harry with intense hostility.
'There was a Regressive element among the volunteers for Colony
Seven,' he said at last. He looked Harry up and down, staring at his
crumpled clothes and shoeless feet in undisguised disgust. 'Our
Genetic Pool has been refined to the ultimate,' Noah almost shouted,
turning upon Vira. 'You must be aware that three random units could
threaten our survival... and the contamination factor... irrevocable
damage may already have occurred.'
       Suddenly there came a gasp from behind Harry. He whirled
about, and was delighted to see that Sarah's eyelids were flickering.
He took her hands. 'Come on, old girl,' he cried. 'I know you can do
it.
       Vira hesitated a moment under her Commander's furious gaze.
Then she said quietly, 'The Council can decide, Commander,' and
walked quickly over to Sarah's pallet, and began monitoring her
progress. 'Your companion had not reached total metabolic
suspension,' she murmured to Harry. 'She will revive soon.'
       Harry took a step towards the Access Chamber. 'We must tell
the Doctor.'
       Noah approached Harry menacingly. 'Where is the third
Regressive?' he demanded.
       'He's having a look at your... er... Solar Stacks,' said Harry in
euphoric relief at Sarah's imminent recovery. 'He reckons they're on
the blink.'
       'The Solar Reservoirs,' hissed Noah. 'He must be stopped.' The
Commander spun round and ran from the chamber.

       His improvised rearrangement of the main power circuits
completed, the Doctor quickly found his way from the Control
Centre down into the very heart of the Satellite. As he opened shutter
after shutter, on his guard for whatever might be lurking on the other
side, he puzzled over Harry's description of the bubbling
phenomenon he had seen, and tried to relate it to the gigantic corpse
they had discovered in the Cryogenic Chamber. He encountered
more and more silver trails criss-crossing the tunnels, emerging from
and disappearing into the grilled openings.
       He soon found himself confronting a large circular door,
similar to that of a strongroom, bearing a stark warning in luminous
stencilling:

                   SOLAR PLASMA CELLS
                EXTREME RADIATION HAZARD
                   FIRST TECHNOPS ONLY

      The Doctor smiled to himself; after a few minutes' juggling
with ear trumpet, pocket magnet and probe, he succeeded in
operating the lock. The door—a fifty centimetres thick Radiation
Shield—swung open smoothly. Cautiously the Doctor entered the
vast hemispherical chamber. His eyes adapted immediately to the
subdued orange glow within. One by one he began examining the
ceramic plasma bottles—translucent spheres five metres in diameter.
      'Well, well,' he murmured, 'the old vacuum plasma method—
with a few little refinements. They must have been in a hurry to leave
Earth. Not a bad lash-up at all.'
      Everything seemed to be in order. Then the Doctor detected,
amid the almost imperceptible humming of the chamber, a brittle
crackling sound, which was growing steadily louder and closer. He
crouched beneath one of the reservoirs and listened. Although there
was no sensation of hotness from the super-heated plasma, the
Doctor knew that even he could not stand exposure to the radiation
for more than a minute or two. But he had to discover what was
causing the colossal power drain in the Systems.
       The crackling sounds came from above. Staring upwards at the
dim outlines of the plasma globes, he suddenly saw the clusters of
pustular matter clinging to several of them, and to the
interconnecting shafts. Stealthily, the Doctor emerged from hiding
and inched his way towards a ladder leading up to the next level.
Crouching close to the treads of the ladder, he reached the second
catwalk safely and began to climb to the third level. Sections of the
metalwork felt tacky, and they glistened with the familiar silver
deposit. When he was halfway up the third ladder, the crackling
sounds suddenly increased and the movement of the jostling,
bursting bubbles quickened.
       Instinctively the Doctor flung himself backwards, just as a
snaking tentacle of globule lashed through the gloom towards his
head. He tumbled heavily down the ladder on to the landing below.
Drenched in sweat, his ears splitting from the harsh crackling and his
head aching from the fall, the Doctor scrambled back into the narrow
space between two reservoirs. He watched in fascinated horror as a
quivering mass of greenish bubbles began to form underneath the
catwalk over him, oozing through the steel mesh. It grew into a
shapeless glob the size of a man; then elongated itself into a droplet.
Just in time, the Doctor ducked back as it whipped out at him with a
vicious crack. Missing its target, it broke into fragments which stuck
to the metal rails, sizzling like hot fat a few centimetres from the
Doctor's face.
       He quickly looped a length of scarf round a stanchion and
dived through the railings of the catwalk, swinging down to the floor.
Darting through the Radiation Shield, he dragged it shut behind him
and ran swiftly back to the Control Centre. The savage crackling of
the globule as it had massed to attack him still filled his head. The
Doctor knew that he must find some way to starve the alien creature
of energy and stop it from multiplying and spreading through the
Satellite; he also knew that to tamper with the Solar Plasma System
could be catastrophic.
       Reaching the Control Centre, the Doctor sought out the Solar
Systems Panel. He stood for a moment staring at the complex
displays; one slip and an irreversible chain reaction would occur. He
decided that the risk had to be taken. He bent over the console and
began to calculate the exact sequence in which the system would
have to be run down.

       'Stand away from the systems console.'
       The Doctor glanced over his shoulder in surprise. He
recognised Noah standing in the entrance to the Control Chamber
Suite. Noah was pointing a small, torchlike weapon straight at the
Doctor's head.
       'Ah there you are, awake at last.' The Doctor smiled. 'I'm just
about to close down the Solar Plasma Systems.'
       'Move away,' said Noah. 'The Terra Nova is ours.'
       'In theory certainly,' agreed the Doctor, turning back to his
task. 'But unless we do something quickly, it will not be yours much
longer.'
       Noah advanced a few paces, levelling the weapon. 'Degenerate
Seventh Colonists,' he sneered. 'Your pathetic attempt at sabotage
has failed.'
       The Doctor turned to face him and stood upright. He spoke
rapidly but calmly. 'There is some alien life-form feeding on the
energy in your Solar Reservoirs, and if we do not stop it at once it
may completely overrun your Satellite.'
       Noah broke into a mocking laugh. 'You and your companions
are the only alien forms here,' he cried. 'It is you who must be
stopped.'
       There was a brilliant sheet of spark from Noah's hand. The
Doctor was momentarily enveloped in a blue aura. He froze, his hand
raised and his mouth half open to speak. He did not move.
                              4
                       A Fatal Wound
       Full of professional admiration, Harry watched Vira moving
calmly about the Cryogenic Chamber, monitoring the progress of her
people as the Revivification Programme entered the final phase of its
preliminary stage. From time to time, he glanced anxiously at Sarah;
she did not appear to be responding to the treatment Vira had given
her earlier. Vira now seemed completely oblivious of them both, and
the Doctor's long absence was making Harry feel extremely uneasy.
Suddenly Sarah began to moan, and her body convulsed. Harry
moved to help her.
       'Do not touch the female,' snapped Vira, without looking
round.
       'Now look here,' said Harry. 'I am a fully qualified physician
and I do think I...'
       'You have no function here,' retorted Vira dismissively. 'You
are intruders.'
       'Charming,' muttered Harry to himself. 'If it weren't for the
Doctor, neither you nor your people would be alive now.'
       'The Commander will not permit contamination of the Genetic
Pool,' said Vira in a hard voice. 'All Regressive influences must be
eliminated.'
       Harry gasped at the sinister tone of her words. At the same
instant he turned, just in time to catch Sarah as she toppled forward.
He eased her gently back into the pallet and checked her pulse. It
fluttered weakly. He looked across at Vira, but she was totally
preoccupied. All at once Sarah screamed—a terrifying hoarse cry
that ripped through Harry's head. He caught her again as she
staggered out of the pallet, staring with wide, panic-stricken eyes at
the corpse of the giant 'locust' creature lying in the shadows. The
shock brought Sarah to in a flash.
       'What... what is it... ?' she whispered, clinging fast to Harry's
arm. He was overjoyed to hear her speak, and put his arm
protectively round her shoulders.
       'Oh, we found it in the cupboard,' he said nonchalantly. 'Sort of
galactic woodworm, old girl.'
       Sarah stared around her open-mouthed. 'Where's the Doctor?'
she asked shakily.
       Before Harry could answer, Vira's voice pierced the quiet
humming of the chamber. 'Where is Dune?' she demanded. Sarah
jumped with fright. Vira was pointing to an empty pallet near where
the Doctor and Harry had found the tacky trail on the chamber floor.
       Sarah glanced at Harry for some explanation, but he was
staring blankly at Vira as she approached them, shaking with anger.
'What have you done with Technop Dune?' she repeated. 'Answer
me.' Sarah leaned heavily on Harry's arm, faint and disorientated.
Her face was white, and she was trembling all over. At that moment,
Noah's voice rang out over the intercom in the Access Chamber.
       'Hear me, Vira... I am in Central Control. I discovered the third
Regressive attempting to sabotage the Solar Power Systems. He has
been dealt with.'
       'That means the Doctor,' Harry whispered as Vira hurried
through into the Access Chamber.
       'Commander, hear me,' they heard her say into the intercom.
'Technop Dune is missing; there is no explanation.'
       'The explanation,' Noah hissed, 'is that the Regressives have
taken him. Proceed with Revivification. I shall inspect the Solar
Chamber...'
       Vira turned to see Harry and Sarah lingering uncertainly 'The
Commander will interrogate you when he returns,' she said, brushing
past them and resuming her Medtech duties.
       Harry started as Sarah suddenly gripped his arm.
       'Come on,' she whispered. Harry looked at her in astonishment.
'We must find the Doctor,' she said urgently.
       'Well... yes, but are you sure you're... you're...' Harry
stammered.
       Sarah smiled broadly. 'Are you all right, Harry?' she asked.
'You look a little pale.'
       Harry was speechless. He shook his head in admiration at
Sarah's remarkable recovery. 'You really are amazing, old girl,' he
chuckled.
       With a glance to check that Vira was occupied, Sarah ran
lightly across the Access Chamber to the panel leading to the tunnel.
'Do you know the way to Central Control?' she whispered.
       Harry pulled himself together. 'I think so...' he muttered.
       Sarah beckoned impatiently. 'Then show me how to open this
thing, and let's go,' she said.

       Noah opened the Radiation Shield and entered the Solar
Chamber. His movements were slow and clumsy, hampered by the
heavy protective suit he now wore. At first, the thick transparent
helmet muffled the vicious crackling sounds echoing round the
chamber, but as Noah advanced further in, they rose to a crescendo.
Noah faltered and stopped. Through the vizor he glimpsed something
whipping towards his face. Restricted by the suit, he had no chance
of twisting aside in time. Something caught the sleeve of his suit and
gouged a deep, scorching tear. Confined inside the helmet, Noah was
deafened by his own scream.
       He staggered backwards down the metal ladder, the torch-
shaped weapon sparking in his hand. His forearm burned beneath the
gashed sleeve. He backed clumsily towards the open Shield, blinded
with sweat and barely conscious. There was a hideous sensation in
his injured arm, as if a column of stinging ants was forcing its way
through the veins. He squeezed through the opening into the access
tunnel and dragged the Shield shut. He leaned against it, gasping for
breath, and tried to remove the glove from his damaged hand, but the
helmet had steamed up and he could not see properly. Whimpering
with pain, he fought to remove the helmet, his spasmodic breathing
echoing inside it. At last the helmet came free and smashed on the
tunnel floor. Noah dropped to his knees, and then slowly keeled over
on his side.
       His eyes bulging with terror, .he brought the injured arm
across in front of his face; the deep tear in the sleeve was filled with
a greenish bubbling pus which, as he watched, seemed to be
absorbed into his arm so that only the blackened gash in the sleeve
remained. With a harsh cry Noah rolled over on to his back, the
injured arm grotesquely fixed in the air. His whole body went rigid.
His arm lost all sensation and he blacked out. A wisp of acrid smoke
curled up from the scorched slit.

        As they warily found their way to the Control Centre where
Noah had reported his encounter with the Doctor, Harry did his best
to explain to Sarah about the Satellite being a kind of 'Noah's Ark'
bearing survivors from Earth, and how she had somehow become
caught up in the works.' For her part, Sarah could remember very
little about her experience in the Cryogenic Suspension System, but
she told Harry as much as she could.
        Harry was relieved to discover that the bulkhead panels
seemed to be designed to operate on a straight-forward 'electric eye'
mechanism when approached from the direction of the Cryogenic
Chamber, and that they opened automatically.
        However, there was a tense moment when he and Sarah passed
through the shutter leading into the Control Centre Access Tunnel.
Harry had passed through first and the shutter had dosed before
Sarah could join him. He waited a few moments for her to operate
the photo-electric cell, but the panel remained tightly closed. Harry
struggled in vain to open it by resting his forehead against the little
copper plate and thinking about something complicated—just as the
Doctor had done—but he did not seem able to generate the correct
brain-waves. Meanwhile, Sarah had approached the 'electric eye' on
the other side of the shutter, and had been startled by a sharp
crackling sound behind her which made her spin round; a wobbling
cluster of greenish bubbles was bursting through a grilled vent in the
floor a few metres from her feet, and forming itself into threatening
serpent shapes. With a shriek she had thrown herself against the
panel, and as it opened, toppled white-faced into Harry's arms.
        In a few seconds they reached the Control Centre. The Doctor
stood smiling at them, his hand raised in greeting. 'Doctor... you're
safe,' Sarah cried, rushing over to hug him. She recoiled in horror
when she realised that something was badly wrong. Harry examined
the Doctor's rigid fingers. 'What's the matter with him... ?' whispered
Sarah.
       'I've no idea,' said Harry, trying to bend the Doctor's arm.
       'Well you're a doctor. Do something,' she cried anxiously.
       Harry frowned. 'It's just as if rigor mortis... but it can't be...' he
muttered. He put his ear to the Doctor's chest, first to the left then to
the right side. 'His hearts are beating,' he said at last with relief.
       Feeling very faint, Sarah sank down on the corner of the couch
beside which the Doctor stood like a statue. She immediately sprang,
to her feet again, recollecting her earlier experience with the Matter
Transmitter. But as she leaped up she lost her balance, grabbed
Harry's arm to save herself and they both collided with the Doctor, so
that he fell sideways. on to the couch. As he fell, his forehead
touched part of the exposed electronic circuitry in the base of the
couch. There was a bright flash and a popping sound. The Doctor
sprang to his feet, clutching his singed forelocks.
       'Ah, Sarah. How nice to see you. Splendid,' he cried. 'Where's
Noah?'
       'Doctor, don't you think you should sit down for a moment?'
said Harry with concern.
       'Sit down?' the Doctor exclaimed, staring incredulously at
Harry. 'At a time like this?' He winced, and clutched his temples. 'I
detest paralysators. Highly unreliable.' He looked around him.
'Where's Noah?' he repeated.
       'He said he was going to examine the Solar Systems,' began
Harry...
       'Quick,' cried the Doctor, striding out of the chamber. 'There
might still be time to save him.'
       Totally bewildered, Sarah and Harry followed. They hurried
along the Cincture Structure Gallery, on their guard against the
crackling, bubbling alien organism whose tracks became more and
more evident.
       'Strange how they've given us the run of the ship,'
       Harry remarked. 'Why didn't Vira try to stop us?'
       'Not her function, Harry,' called the Doctor over his shoulder.
'By the Thirtieth Century, human society has become highly
specialised. Vira is a Medtech; we, I suspect, are an Executive
problem.'
       'Correct, Doctor, but not a difficult one. You can be easily
eliminated.' The snarling voice seemed to come from nowhere. They
stopped in their tracks as Noah, still clad in the radiation suit,
emerged without warning from an alcove in the gallery and barred
their way. His left hand was held behind him, in his right he
brandished the paralysator gun.
       'I am delighted to see you again, Noah,' smiled the Doctor,
raising his hat. 'I suggest that without more ado we put our heads
together and devise a prompt solution to what is undoubtedly your
most serious problem... Unless we destroy the organism in the Solar
Chamber it will...'
       Noah gestured sharply with the paralysator. 'We will return to
the Cryogenic Section,' he ordered. Harry and Sarah looked at the
Doctor, uncertain how he would handle this impasse. Suddenly the
Doctor turned on his heel and set off along the curving gallery at a
furious pace.
       'You're absolutely right,' he called. 'There's not a moment to
lose.'
       As they entered the Cryogenic Chamber, closely followed by
Noah with the paralysator still levelled at their backs, Vira was
assisting a tall, blond young man out of his pallet. As soon as he saw
Noah he threw up his arms in front of his face and cowered back into
the alcove.
       'No ,.. No,' he screamed, his face contorted in panic. 'Keep
away... Keep back.'
       'What is wrong?' demanded Noah in a hollow voice. The
young man hid his face, trembling and whimpering. Vira looked
shocked.
       'I do not understand, Commander,' she murmured. 'His
responses were normal.' She turned to the terrified youth. 'Libri... it is
the Commander. Commander Noah... do you not remember?' The
young man relaxed a little, and then lowered his arms.
       'I... I am sorry, Commander,' he said. 'For an instant I saw...
you were... I saw something.'
        The Doctor stepped eagerly forward. 'What did you see?' he
asked.
        'Silence,' Noah hissed, threatening the Doctor with the
paralysator, his left hand still concealed behind him.
        The Doctor looked hard at Noah. 'What have you done to your
hand?' he asked calmly.
        'No further warnings,' shrieked Noah hoarsely. He beckoned
Libri to him. Hesitantly Libri obeyed. Noah handed him the
paralysator. 'Take these Regressives to an Abeyance Unit,' he
ordered. 'They will remain there until the Council has convened. If
they are disruptive, eliminate them.'
        Everyone stared. at Noah. His harsh manner and hoarse voice
contrasted violently with the restrained dignity of Vira and Libri.
Vira moved towards Noah. 'Commander,' she began, 'we should
not...' but Noah ignored her.
        'The Systems must be closed down. Revivification must cease
at once.'
        Vira and Libri exchanged shocked glances. 'Why,
Commander?' said Vira in disbelief.
        'It is my instruction,' Noah shrieked, his voice breaking 'The
Programme is revised. I am Commander.'
        Vira gestured round the shadowy, echoing chamber.
'Commander, the First Phase has hardly begun; we have no Technops
to operate the Systems.'
        'I shall operate the Systems,' snarled Noah, shuddering as some
kind of spasm passed through him.
        'Without First Technop Dune we cannot hope to succeed,' said
Vira firmly.
        'Who?' whispered Noah, trembling.
        'Commander, I reported to you; Dune is missing.' Vira
indicated the vacant pallet.
        'You are mistaken, Vira. Dune is here.' Noah's whisper rasped
and echoed around them. They stared at him. 'I am Dune,' he
croaked, his face clouding as if something within him was struggling
to emerge, and his conscious mind was fighting it back.
       Vira suddenly moved towards him, but he backed away.
'Commander, you are injured,' she cried. 'You are unwell.'
       'Yes... No... I... Hear me...' Noah faltered, his face glistening
with perspiration. His body seemed twisted slightly inside the
cumbersome radiation suit. 'Revivification must be discontinued
now... now...' He backed awkwardly towards the Access Chamber,
mumbling and whispering unintelligibly. All at once, with a gasp of
agony, he turned his back to them. He seemed to be tearing at his
injured arm. As he stumbled away through the Access Chamber he
cried out, as if uttering a curse, 'No more aliens...'
       The Doctor looked straight into Libri's eyes. 'Noah must be
stopped,' he said. 'There was a systems fault during his
Revivification—his brain is damaged.'
       Vira went over and spoke to the young Medtech in an urgent
whisper. 'Libri, there is no procedure for arresting Revivification. It
would be fatal.'
       Libri met their gaze calmly. 'Noah is our Commander,' he said.
       The Doctor edged towards him. 'Can you be sure of that,
Libri?' he asked. Libri flourished the paralysator at him. The Doctor
stepped a little closer; Sarah caught Harry's sleeve in apprehension.
The Doctor slowly took a large pocket watch from his jacket. He let
it swing gently on the end of its chain in front of Libri's face. He
spoke in a soft, rhythmic voice. 'Libri.... when you first saw Noah...
you had a subconscious impression... of something horrible... That
was not your Commander... was it?'
       Libri gazed at the glittering watch, mesmerized. Then, when
the Doctor finished speaking, he looked up into the Doctor's huge,
piercing eyes. 'Noah must be stopped,' he cried, and rushed out of the
Cryogenic Chamber in pursuit.
       At once the Doctor darted across to Technop Dune's empty
pallet and began poking about with the telescopic probe. Almost
immediately, he took out the magnifying glass and peered through it
at the end of the extended rod. 'Of course... of course. Why didn't it
occur to me before?' He strode across the chamber towards the
gigantic corpse lying on the far side of the adjacent bay.
       Vira swiftly overtook him, and stood in his path. 'It is not
advisable for you to leave,' she warned:
       The Doctor handed her the magnifier, and held up the point of
the probe to examine. Impaled on it was a fragment of colourless,
rubbery membrane. 'Perhaps this will convince you that we are not
your enemy,' he said.
       Vira stared at the fragment of tissue. 'What is it?'
       The Doctor knelt down, and probed about in the collapsed
abdomen of the monstrous creature. 'It is almost too horrible to
contemplate,' he murmured.
       Completely mystified, Harry and Sarah watched over his
shoulder. After a few moments, the Doctor stood up. 'As I suspected,
the egg-tube is empty,' he announced. 'Egg-tube?' gasped Vira.
       The Doctor gazed down at the corpse. 'The Queen Colonizer...
the Progenitor,' he said solemnly. They all stared at him. He looked
round at them one by one. 'Have you heard of the Eumenes?' he
asked in a hushed voice.
       'It's a species of wasp,' said Harry. 'It paralyses caterpillars and
lays its eggs in their corpses. When the larvae emerge they have an
immediate food...' Harry's voice trailed into silence. He looked at the
Doctor in horror.
       Vira put her hands to her face, speechless. Sarah covered her
mouth as if she were going to be sick. The Doctor walked round
them, deep in thought. 'Strange how the same life-patterns recur
throughout the Galaxy...' he mused. 'Dune was Power Systems
Technician, I imagine,' he said, pausing beside Vira. She nodded.
'The larvae went straight to the Solar Stacks,' the Doctor continued.
'They absorbed Dune's knowledge, as well as his tissues.'
       Vira stared across at Dune's pallet, then around the huge
chamber at the thousands of sleeping humans. Suddenly she seemed
to relax. 'The Creature's larvae will perish in the Solar Chamber,' she
said. 'The radiation will destroy them.'
       The Doctor shook his head. 'On the contrary,' he said. The
larval organisms are feeding on the Solar energy, and becoming more
powerful every minute.'
       Libri entered the Control Centre seconds behind Noah. He
stood transfixed in the entrance, watching his Commander staggering
about the chambers, his breath rasping and rattling, eyes rolling and
body contracted into a grotesque posture. His injured arm was held
up across his face, and with his other hand Noah repeatedly tore at
the glove. Suddenly he stopped. Shaking his head slowly from side to
side he lowered the injured arm in front of him. With a sound of
water dripped into boiling fat, green pus began to bubble out through
the seams of the glove, the thick material splitting like paper.
       'Commander,' gasped Libri, stepping forward.
       With a hideous, shrieking cry Noah reeled to face him. 'Give
me the paralysator,' he croaked.
       Libri backed away a pace. 'You... you are not well,
Commander,' he stammered.
       Struggling to control his body, Noah advanced on him. 'I order
you...' he cried.
       In his eyes Libri saw desperation and fear, and that made him
hesitate for a fatal fraction of a second. Noah seized the weapon with
his good hand and tried to twist it from Libri's grasp. The young
Medtech stared at his leader like a hypnotised animal. Then
something flew through the air and cut him across the face. He fell
back, screaming and clawing at the intense burning sensation in his
eyes.
       Noah wrenched the paralysator from him, and pressed the
trigger at point blank range. Libri's body was hurled across the
chamber in a succession of frozen shapes as pulse after pulse cracked
into it. When the sparking ceased, Noah stared in terror at the
smouldering body of the young man welded to the panelling. Then
he dragged himself through into the inner chamber, the suppurating
stump of his left hand raised like a club. He hovered grotesquely over
the Cryogenic Systems Panel, moaning in anguish. His right hand
clung fiercely to the sleeve of the injured arm, fighting to prevent it
from touching the sensitive controls...
       The chambers and tunnels of the Satellite suddenly echoed
with a clear, crystal-toned chime which was followed immediately
by a calm female voice. 'Greetings to the Terra Nova... You have
slept for longer than the recorded history of Humanity... you awaken
now in the dawn of a New Era...' Noah stood immobilised in a
twisted posture, his face betraying recognition of the High Minister's
voice, and the shock of the returning memory of his own humanity.
The voice echoed on... 'You will return to an Earth that we cannot
imagine... a world that is dead... You must make it flourish and live
again...'
       Noah's body twisted this way and that as the human and the
alien fought for supremacy within him. His mind was filled with the
great purpose about which the High Minister was speaking, yet he
felt himself inexorably overwhelmed by the destructive alien
consciousness that was steadily possessing his mind and body. One
moment he found himself listening to the High Minister's words with
hope and longing for the green Earth again; then he would be seized
with a dizzying sensation of dark emptiness and a fierce hate for all
humans. His upright posture suddenly seemed unnatural; he stumbled
forward to his knees as the voice of the High Minister, recorded
thousands of years earlier, rose to an impassioned climax. He began
to beat the stump of his left arm against the edge of an instrument
console. The heavy protective suit seemed to be crushing the breath
out of his body; he felt something within him instinctively struggling
to break out as if from a shell. His alien hand hissed and crackled...
       '... and so, across the chasm of the years, I send to you the
hopes of all Humanity for a safe landing... safe landing... safe
landing...'
       The High Minister's words became an exuberant refrain in
Noah's ears. He crawled across to the opening which connected the
two chambers of the Control Centre, intent on vengeance against the
hated Humans. He raised the paralysator, still gripped in his right
hand, and directed the relentless pulses of energy at the body of the
young Medtech until it had completely disintegrated into nothing.
Then the weapon clattered from his grasp as Noah's human
awareness gained supremacy again.
       He backed into the smaller chamber, his mind struggling to
overcome the urge of his injured left hand to wreck the Cryogenic
Systems Panel. The arm seemed to have an existence of its own,
independent of his control. As he stared at it, the sleeve suddenly
split wide open, spilling out a stream of viscous matter which rapidly
hardened into a glistening, cellular tissue.
       It was the flesh of a Wirrrn...
                             5
                         The Wirrrn
       The Doctor and his companions stood silently as the serene
voice of the High Minister flooded the Cryogenic Chamber. Vira had
ascended to the second level of pallets, where the multiple humming
of the Re-vivification process was increasing little by little as the
occupants were brought gradually back to life. The Doctor had been
squatting thoughtfully beside the crumbling remains of the corpse,
poking about the exposed viscera of the alien creature. Harry and
Sarah had been detailed to search for more of the trails left by the
larvae, and to check for any other-empty pallets where the creature
may have laid its eggs.
       'Sort of pre-match pep talk,' whispered Harry, as the High
Minister drew towards the end of her message. Sarah was listening in
rapt attention; she had heard the mysterious voice before, but where?
Vira gazed slowly round at the ranks of her people. She could not
understand what had happened to Noah, why he had ordered
Revivification to cease. As she listened to the High Minister, she was
filled with a renewed sense of her great mission.
       The High Minister's voice was brutally interrupted by a harsh,
grating whisper which broke into sudden shrieks and gasps,
becoming incoherent and then lucid again. '... Vira... Vira... Hear
me... Expedite Revivification... Initiate the Main Phase now...'
       Vira looked utterly bewildered. 'Noah... Commander,' she
cried, 'I do not understand...'
       'We... you are in danger... Take our... your people to Earth
before they... before we...' Noah's voice became a distorted roaring.
Vira turned from side to side, staring into the dark upper reaches of
the chamber as if seeking Noah there. 'They... We are here... in the
Terra Nova,' the rasping whisper continued. 'We shall absorb the
humans... the new Earth will be ours...'
       Vira covered her face, rocking herself to and fro in terrified
incomprehension.
       'We are in... Wirrrn my mind... no time... Libri is dead... the
Wirrrn will absorb... Wirrrn will absorb the humans...' The hoarse
whisper of Noah's threat reverberated for some time. Then silence
fell over the vast chamber.
       It was broken at last by the Doctor. 'The Wirrrn... Wirrrn...
endo-parasitism... multi-cellular larvae...' he muttered, as if trying to
recall something from the depths of his colossal, encyclopaedic
memory.
       'Does that mean they'll literally eat us alive?' shuddered Sarah.
       The Doctor nodded gravely. He swept his long arm in a broad
gesture round the Cryogenic Chamber. 'The Revivification process is
much too slow,' he warned. 'If we do not destroy the Wirrrn larvae
before they develop into pupae—none of us will survive.' He crossed
the chamber to the base of the elevator shaft, where Vira lingered
uncertainly. He took her gently by the arm. 'If we can confront Noah
in time—while he still retains some vestige of his humanity—we
may be able to discover a way of fighting the Wirrrn. Come.'
       Vira held back. 'I cannot leave until the last of the Technop
Personnel have safely revived,' she protested.
       The Doctor looked earnestly into her face. 'You are the only
one of us that Noah—or what is left of Noah—will trust. You must
come with me—for the sake of your people.'
       The Doctor quickly persuaded Harry that he had observed
enough of the Revivification Process to take over from Vira for a
short time, with Sarah's assistance, of course. Then he led Vira firmly
out through the Access Chamber in pursuit of Noah.
       As they were whisked along the Access Tunnel on the
conveyor, the Doctor outlined his theory. 'I postulate a multi-nucleate
organism with a shared consciousness,' he concluded. 'The larvae
clustered in the Solar Chamber in order to pupate and we—first
myself, then Noah—disturbed them.' They had reached the
Decontamination Airlock which sealed off the Cryogenic Sector. As
the shutter opened they came face to face with Noah. He was
hunched in the confined space of the cubicle, still wearing the white
radiation suit which was now split open down the entire left side and
oozing the green, treacly bubbles of the parasite larvae. Choking
fumes from the smouldering suit curled around him.
       Conquering her fear and revulsion, Vira stepped towards her
Commander with outstretched arms.
       'Do not touch me,' Noah rasped. His face was turned away
from them, but he covered them with the paralysator.
       The Doctor seized Vira's arm and pulled her behind him. He
then spoke rapidly to Noah. 'Tell us one thing, Noah. How much time
do we have?'
       Slowly Noah turned his head fully towards them. The whole of
the left side of his face was transformed into a shapeless, suppurating
mass of glistening green tissue, in the midst of which his eye rolled
like an enormous shelled egg. As they stared at him horrified they
could almost detect the spreading movement of the alien skin.
       'It... it feels near... very near... now,' he croaked. As he tried to
speak, a ball of crackling mucus welled out of the dark slit that was
his mouth and trickled down the front of the suit. He stumbled
forward. 'Vira... Vira...' He threw the paralysator at Vira's feet. 'For
pity's sake... kill me... kill me now,' he pleaded, his voice barely
intelligible. Then he reeled back with an appalling shriek into the
airlock as, with a crack like a gigantic seed pod bursting, his whole
head split open and a fountain of green froth erupted and ran sizzling
down the radiation suit, burning deep trenches in the thick material.
The shutter closed.
       Vira stared at the closed panel, pale and shaking. 'I am sorry,'
she said at last. 'I showed weakness.'
       'No, I could not have done it either,' said the Doctor, picking
up the weapon. 'Come, there is little time.'
       For a moment Vira did not move. 'Noah... Noah and I were
pair-bonded for the new life,' she said. Her eyes were full of tears.
The Doctor gently led her away, back down the Access Tunnel to the
Cryogenic Chamber.

      Much to their own surprise, Harry and Sarah had successfully
supervised the revival of two Technops: Lycett and Rogin. At first
dazed and suspicious, the technicians had soon revealed themselves
to be almost friendly after Harry's and Sarah's breathless
explanations. They were much less formal than Vira had been, and
Rogin did not seem too surprised that things had gone wrong.
       'We should have taken our chance in the Therm Shelters, and
stayed on Terra Firma,' he said wistfully.
       'How much Anatomy do you remember, Harry?' the Doctor
cried, sweeping into the Cryogenic Chamber and going straight over
to the corpse of the Wirrrn Queen.
       'Quite a bit, I hope,' said Harry, joining him. 'But you'd need an
Entomologist for that thing.'
       Vira greeted the two Technops with obvious relief, glad to
have the company of her own people again. 'We will commence
Main Phase at once,' she ordered, leading them to the Access
Chamber Control Suite.
       'But the safety procedures...' protested Lycett, shocked.
       'We shall override them,' said Vira. 'I am Commander now, it
is my decision. Take your operating stations.'
       'Curious lung structure,' remarked Harry as he watched the
Doctor probe through the remains of the Wliiin Queen for some clue
as to its origin and possible weaknesses.
       'A superb adaptation,' the Doctor agreed. 'Its lungs recycle the
creature's wastes... almost certainly by enzymes of some kind...
carbon dioxide back to oxygen...'
       'Like plants,' suggested Sarah, craning to see.
       The Doctor turned his attention to the huge head. 'Exactly,
Sarah... It seems capable of existing in Space, just occasionally
visiting a planetary atmosphere for food and oxygen.'
       'The way a whale rises to the surface...' Sarah added.
       The Doctor was staring at the Wirrrn's gigantic yellow eye.
Suddenly he leaped to his feet and rushed through into the Access
Chamber, where Vira and the two Technops were initiating the Main
Phase.
       'Wait,' he shouted. 'The Main Phase must wait.'
       Vira turned to the Doctor in astonishment. 'But Noah said we
should expedite Revivification and get our people to Earth '
       The Doctor waved his arms impatiently. 'The process is much
too slow,' he cried. 'The Wirrrn larvae will have pupated to imago
long before the last of your people are fully revived. We may have
only hours before the Wirrrn overrun the Satellite.'
       Vira looked defiantly at the Doctor. She seemed to have
regained her former cold authority. 'You have an alternative plan?'
she challenged.
       'The larvae must be entering the pupal stage now,' explained
the Doctor. 'Before they develop into adult Wirrrn form, they will be
relatively dormant. If we can only discover their weakness we may
be able to destroy them. I wonder...
       'I need everyone's assistance,' he suddenly shouted, bolting
back into the Cryogenic Chamber. For a moment nobody moved.
Sarah's face lit up in anticipation as she realised the Doctor was
about to launch one of his improvised experiments. For the next five
minutes the Doctor rushed from one chamber to the other, issuing
rapid instructions. Harry was persuaded to try his surgical skills in
removing a section of the Wirrrn Queen's giant brain.
       Vira reluctantly ordered Rogin and Lycett to abandon the Main
Phase procedure. At first they resisted, but they grew more and more
co-operative as they realised the extent of the Doctor's knowledge.
They agreed to assist him in rigging up a Neural Amplification
System...
       After an hour of frenzied activity, the Doctor made the final
adjustments to his 'apparatus'; what looked like a lengthy piece of
crochet, made out of yards of cable and connectors, hung from one of
the Access Chamber Video Cabinets. Several wires stretched from
the incredible tangle across to a large segment of the. Wirrrn's brain
tissue. The electrode terminals on the ends of the wires were inserted
into various parts of the gelatinous grey substance.
       Vira had stood apart from the others, looking on suspiciously
while they worked. 'What are you attempting to do?' she asked
sceptically as the Doctor completed his adjustments.
       'In certain kinds of tissue, neural impressions can sometimes
be revived by carefully controlled stimulus...' began the Doctor.
       'I've never heard of that,' Harry interrupted, frowning.
       'Yes, there were theories,' said Vira in a cold, clinical voice.
'But our research was in its infancy when the Earth had to be
evacuated.'
       The Doctor grinned mischievously. 'Well, you see I have
something of a head start in such matters.' He winked at Sarah, who
winked back.
       'Gypsies used to believe that the eye retained its last image
after death,' she said. Vira stared at her impassively.
       'Anyway, here goes,' said the Doctor; signalling to Rogin to
switch in the video unit and the amplifier lash-up. 'It should at least
give us an idea of the Wirrrn Queen's last moments.'
       The video screen was at once mottled with white flashes of
static. With great care the Doctor altered the positions of the
electrode probes inserted into the Wirrrn's brain tissue. The screen
showed nothing but dizzy zig-zag patterns as the Doctor connected
different areas of the Wirrrn Queen's brain to his 'machine'. He
sighed with disappointment.
       'It's no good,' he muttered. 'The neuron matrix isn't sensitive
enough. It isn't going to work.' The Doctor stared sadly at his
'crochetwork', his chin sunk on his chest.
       'I am going to link in my own brain,' he announced suddenly.
       Vira immediately stepped forward. 'I cannot allow it,' she
cried. 'The power could burn out a living brain.' But the Doctor was
already rummaging about among the circuitry.
       'An ordinary brain, I agree,' came his muffled voice from
inside the video cabinet 'But mine is rather exceptional.' He grinned
over his shoulder before ducking back in again.
       'Doctor, it's an appallingly dangerous idea,' Harry objected.
       The Doctor stood up. 'It's the only way,' he said.
       The others watched apprehensively as Rogin and Lycett
attached electrodes to the Doctor's temples, and connected the wires
into the maze inside the cabinet and to the probes stuck into the
Wirrrn brain. The Doctor pointed to the video cabinet, to the brain
tissue, and then to his own head. 'Piggy in the middle,' he smiled.
       Sarah shuddered. 'Do you have to do this, Doctor?' she
pleaded.
       Vira moved between the two Technops and the equipment. 'I
forbid this,' she said. But Rogin and Lycett seemed to be fascinated
by the Doctor's plan.
       The Doctor gestured towards the Cryogenic Chamber,
humming faintly in the background. 'The outcome of this experiment
may save the Human Race,' he said. 'If it fails, then at least only the
six of us will suffer.' He settled himself into one of the control
console seats. 'It may be a trifle irrational of me,' he smiled, 'but
humans are quite my favourite species.' Then his face grew deadly
serious. 'Tie me to the chair,' he ordered.
       The Doctor was soon secured to the seat with a variety of
complicated nautical knots tied by Harry in the thick insulated wire.
The Doctor told Vira to take the paralysator from his pocket. 'Do not
hesitate to destroy me should anything go wrong.' Sarah looked at
Harry in horror as Vira took the weapon without a word.
       'Switch on,' said the Doctor. Lycett and Rogin operated a
sequence of buttons. The Doctor's body shook and then arched
sharply over the back of the seat. His eyes bulged out of their
sockets, his mouth gaped, and he uttered a chilling gasp. Then he
slumped heavily forward.
       Vira moved closer to Harry and Sarah. 'He is joining his mind
to the Wirrrn's,' she murmured. 'If the experiment works, he may
remain part of the Wirrrn's consciousness for ever.'
       Following the Doctor's instructions, Sarah and Harry, each
holding an insulated electrode, systematically probed the lump of
jelly-like matter from the Wirrrn's brain. Occasionally, the Doctor's
limbs jerked; his head snapped suddenly upright, then lolled forward
again on to his chest. On the video screen the flashes of static began
to form vague shapes which dispersed and re-formed rapidly, as if
some image was trying to establish itself. Sarah and Harry forced
themselves to continue, despite the Doctor's agonized gasps and
spasms as they moved the electrodes.
       Rogin suddenly pointed to the screen. 'Look,' he cried. 'It is
working.'
       A faint, ghostly outline was steadily resolving into a clearer
and clearer picture. The Doctor uttered brief whimpering sounds, as
if willing the image to become more sharply defined.
       As they watched the screen with bated breaths, they heard a
distant hissing and buzzing from the Cryogenic Chamber. Rogin and
Lycett leaped to their feet. There was a deafening noise, like the
cracking of an ice floe, followed by the sound of a damp fire
crackling.
       'What is that?' whispered Vira.
       The two Technops rushed through into the adjacent chamber.
The others remained 'gazing at the screen where the shadowy image
had sharpened into a distinct picture of a massive Satellite revolving
slowly against the heavens like a giant spinning-top. The central hub-
structure was composed of a cluster of gigantic tubes, bristling with
antennae and reflector dishes. The radial tunnels, or spokes, which
ran outwards to the great circular rim, swelled here and there into
spherical chambers and sub-structures, all inter-connected with
glinting steel-lattice framework.
       The Doctor sighed, as if with satisfaction. Sarah and Harry
noticed, that he was smiling, and rocking his head gently from side to
side. On the screen the image of the Satellite was also swinging in
the same rhythm. It came steadily closer until the whole screen was
occupied by a close-up of a kind of entrance hatch. The Doctor began
to pant, as if in anticipation. Tentacles snaked into view in the
foreground of the picture and fastened themselves about the steel
hand-holds positioned round the edge of the. airlock.
       'Look out, Lycett, behind you...' came Rogin's sudden shriek
from the Cryogenic Chamber. Vira spun round.
       'What... what is it... ?' Lycett's cry of incomprehension rose to
a piercing scream that rang through the chambers. For a second,
Sarah and Harry stood transfixed as Lycett's cries of agony combined
with the Doctor's strange moans into a grotesque medley of sounds.
Then Harry sprang to life and rushed through into the Cryogenic
Chamber. He caught a momentary glimpse of the glistening,
bubbling creature he had seen before in the gallery. As it rolled in a
great hissing ball towards him, he collided with Rogin who hurled
him back into the Access Chamber and swiftly operated the shutter
control. As the panel glided shut, they all watched the heaving,
crackling mass wobbling across the floor towards the narrowing gap.
The panel closed just in time.
       'Lycett's been absorbed by the larvae...' screamed Rogin.
       Harry dived for the video console. 'Stop the experiment... let's
get out of here.'
       Sarah threw herself forward, barring his way. 'No, Harry... you
could kill the Doctor if you interfere With the circuits,' she cried.
       Vira gave orders in a clear, firm voice. 'Rogin: the Armoury.
Bring the Laser Lances.' Rogin ran out into the Access Tunnel. Vira
turned to Harry who was anxiously eyeing the grilled duct-openings
set high in the walls of the Access Chamber; he knew that at any
moment the larvae might burst in upon them. 'Go with Rogin,' she
commanded. Harry glanced inquiringly at Sarah. She hesitated, then
nodded.
       'Good luck, Harry,' she said.
       'And to you, old girl,' he replied, spinning round and out in
pursuit of Rogin.
       As the panel closed behind Harry, Sarah looked back to the
video screen. The Doctor had grown strangely silent, and on the
screen a blurred and bulbous image of the Control Centre had
appeared. The image swung up and down, and from side to side, as if
showing the view through the eyes of some-thing which was moving
slowly and awkwardly about the chamber. Suddenly, the screen
whitened with a blinding glare. The image of the Control Centre
reeled wildly about. Burst after burst flashed over the screen.
       The Doctor began to struggle violently, fighting against the
tight loops of wire which bound him to the chair, his face folded in
pain. In the foreground of the picture, Sarah and Vira saw a blur of
tentacle shapes flourishing defiantly. Sarah glanced from the screen
to the Doctor's thrashing limbs; then she stared at the inert lump of
the Wirrrn's brain tissue.
       'It's the Wirrrn Queen...' she gasped in horror, pointing to the
video screen.
       The Doctor uttered terrifying cries as, on the screen, the
Electronic Guard discharged its lethal bolts at the Wirrrn Queen,
which was now fighting its way into the second Control Chamber...
showing them all exactly what had happened in reality. Once again,
the Doctor began to breathe in hoarse panting sounds; his head
nodded eagerly, and his hands made rapid gripping movements in the
air. As they watched, Sarah and Vira saw the tentacles come into
view again; they began prising open a section of control panelling.
Thick bundles of cables were ripped from their mountings. The
Doctor's body became hunched, his jaw tensed open. Then, with a
grotesque growling noise, he snapped his teeth shut; on the screen,
severed cable-ends flew in all directions. Then the picture dissolved
into static.
       Sarah felt Vira's hand grip her arm sharply. She had heard it
too, a distant cracklinglike a bonfire at the end of a long tunnel. They
stared up at the vents...

        Harry and Rogin emerged from the Armoury carrying short,
rifle-like objects with dish-shaped shields fitted round the barrels. As
they raced round the Cincture Structure Gallery, Rogin explained to
Harry how to operate the deadly laser guns. They had to pass through
the junction section where the Access Tunnel to the Solar Chambers
joined the curved gallery of the Cincture Structure. As the shutter
opened, they found themselves facing a monstrous apparition. Noah,
his back hunched menacingly, glared at them with the huge ochre-
coloured eye which occupied the whole of the left side of his head.
The entire left side of his body had swollen and burst through the
radiation suit, and the skin was hard and polished. In place of his left
arm, three stumpy tentacles thrashed about, centimetres from their
faces.
        'Human fools... ' Noah's hideous croaking made the hair rise on
Harry's neck. Rogin fired his laser lance at pointblank range, cutting
a deep trench in Noah's glossy, shell-like body. Noah reeled back
against an observation port in the outer wall of the gallery. Pressing
themselves to the inner wall, Harry and Rogin inched their way
through the bulkhead panel, their weapons scoring a macabre criss-
cross pattern in Noah's side. They managed to slip past him, just out
of reach of the knife-like hairs bristling over the jabbing tentacles.
       'You... cannot... stop us...' Noah croaked, turning his head as
the panel began to close between them. Rogin gasped, and stopped
firing as he glimpsed the still recognisable features of his
Commander staring at him in agony. Then he fired a last burst of
laser as the shutter slid home.

       For a few seconds, Sarah and Vira had forgotten the Doctor as
they stared fearfully up at the wall vents of the Access Chamber; the
crackling sounds were growing louder every second, and the closed
panel into the Cryogenic Chamber was beginning to vibrate like a
drumskin, as if something was beating violently on the other side.
Then Vira suddenly gestured in horror at the video screen. 'Dune...'
she gasped. '... Technop Dune...' On the screen Sarah saw the image
of a young man, dressed in the Tech Personnel uniform, lying
helplessly in his pallet. The image came nearer and nearer. Tentacles
reached out and opened the pallet shield.
       Sarah struggled to calm the Doctor. His face was running with
sweat and his teeth were chattering. He began to moan over and over
again.
       '... Wirrrn .'.. Wirrrnwirrrn... the... Wirrrn...' Sarah tore the
electrodes from the Doctor's head and tugged feebly at the tight knots
securing him. She turned to Vira.
       'Help me with him,' she implored.
       Vira was staring at the blank screen. 'That... that was Dune,'
she whispered, her voice filled with shock and outrage. She looked at
the Doctor's shuddering body. 'Stand away,' she ordered Sarah, who
glanced up to see her levelling the paralysator directly at the Doctor.
       'No... No, you can't...' she screamed at Vira.
       'Stand away,' repeated Vira. 'The Doctor's mind has been
possessed by the Wirrrn. He must be eliminated.'
       Sarah threw herself at Vira and tried to wrest the weapon from
her strong fingers. They struggled desperately while the Doctor
remained slumped in his chair, moaning quietly as if in a trance.
       'Wirrrn... wirrrnwirr...'
       Then, from one of the grille-covered ducts above them, there
erupted a mass of crackling froth. Sarah shrank down behind the
Doctor's motionless body; Vira fired the paralysator at the gathering
ball of larvae quivering over them. The weapon had no effect.
       Sarah screamed in the Doctor's ear. 'Doctor, please help us...
help us, Doctor...' as the crackling grew to a deafening pitch all
around them. The panel sealing off the Cryogenic Chamber began to
warp and shudder; round its tightly fitting edges the larvae were
oozing slowly through. Vira backed away, covering Sarah and the
Doctor, and firing the useless paralysator at the apparently
indestructible 'creature'.
       'The panel is failing,' Vira cried. The shutter folded up like
melted plastic. In the entrance to the Cryogenic Chamber there hung
a sizzling curtain of globules, all bursting and multiplying. Whiplash
tentacles formed out of the undulating mass and flew towards them...
                          6
                   Time Running Out
       Harry and Rogin rushed into the Access Chamber just in time
to slice through the fronds of larvae with the laser guns. The
smouldering fragments stuck like dried glue to the floor, centimetres
from Vira's feet. Raking the clustering larvae with the silent and
invisible laser beams, they disintegrated the globules as easily as if
they were cutting through snow with jets of water. The chamber was
soon filled with a choking and sickening smoke. At once the larvae
began to retreat through the ducts; the nightmarish curtain hanging in
the entrance to the Cryogenic Chamber shrank away. Harry and
Rogin advanced, forcing the larvae back.
       The Doctor stood up, effortlessly snapping the wires that had
confined him. He began to lurch towards the retreating larvae with
outstretched arms.
       'Doctor... Doctor, come back,' screamed Sarah, but the Doctor
stumbled heedlessly forward as if obeying some primitive instinct.
       'Get back, Doctor,' shouted Harry as the Doctor crossed into
his line of fire. A corner of the Doctor's jacket was sliced off by
Harry's laser and fell in a smouldering spiral. Sarah had dived
forward and she brought the Doctor down with an unorthodox but
effective rugger tackle. He fell with a crash.
       'Bravo, old girl,' yelled Harry, as he and Rogin leaped over the
Doctor's prone body in pursuit of the straggling remains of the
Wirrrn larvae, rapidly retreating into the Cryogenic Chamber.
       For a few seconds, the Doctor lay quite still. Sarah bent over
him anxiously. Vira was covering him with the paralysator. Suddenly
he leaped abruptly to his feet: 'Good morning, Sarah. Is it time to get
up?' he asked brightly.
       Sarah hugged the Doctor, tears of relief in her eyes. 'Doctor
you... you were nearly...' she stammered, scarcely able to speak.
       The Doctor patted her on the head abstractedly, and seated
himself comfortably at the control console. He took out the scorched
bag of jelly-babies from his damaged pocket, prised one from the
congealed mass, popped it into his mouth and offered the bag
absently to Sarah. 'Breakfast?' he asked.
       Sarah shook her head. 'No thanks,' she grimaced. 'They remind
me too much of that larvae stuff.'
       The Doctor stared at the shapeless lump of melted sweets.
'Why don't they wait?' he murmured to himself. 'In their adult form
the Wirrrn will be far deadlier.'
       'How many of them will there be?' said Vira. She had lowered
the paralysator, but she watched the Doctor warily, still unsure of
what effect the experiment might have had on him.
       The Doctor chewed away thoughtfully. 'At a hatching...
perhaps a hundred... possibly a thousand,' he said quietly. Just then,
Harry and Rogin backed into the Access Chamber, covering the
entrance to the Cryogenic Chamber which was once again humming
gently to itself.
       We'll be ready for them,' Harry said grimly, obviously elated
by their spectacular victory with the laser guns.
       The Doctor shook his head. 'The lances will be virtually
useless against a swarm of fully mature Wirrrn,' he warned.
       'Then how can we fight them?' said Sarah at last.
       The Doctor glanced at the lump of Wirrrn brain, bristling with
electrodes on the control console beside him. 'Electricity of course,'
he shouted. 'I remember now—it was the electromagnetic OMDSS
that killed me... I mean the Wirrrn Queen,' he added hastily, noticing
the paralysator still firmly gripped in Vira's hand.
       'Yes, we saw.' Sarah pointed to the video screen. 'And you
were correct, Doctor,' said Vira. 'Technop Dune was the host for the
Wirrrn eggs. We saw that too.'
       'But how did the Wirrrn Queen get into the Cryogenic
Chamber?' asked Harry, shuddering at the recollection of the dead
creature toppling out on him.
       'The most tenacious willpower,' replied the Doctor. 'I could
feel it fighting off death until it had spawned; until its task was
completed.'
       He stood up, stuffing the sweets back into his coat. 'We must,
get back to the Control Centre,' he said. 'There should be some way
of electrifying the Infrastructure and the Solar Chamber from there.'
He strode towards the entrance to the Access Tunnel.
       'Noah's out there,' Harry cried, barring the Doctor's way. He
quickly related their recent encounter with Noah.
       The Doctor slapped his forehead. 'Of course,' he said. 'That's
why the larvae emerged now; they can bypass the pupal stage by
taking over fully conscious living tissue—like Noah's body. That
way they can accelerate the transformation into mature Wirrrn form.'
He glanced towards the Cryogenic Chamber. The panel lay buckled
beside the entrance. 'We've won a breathing space, but we're trapped.'
His eyes roved around the Access Chamber, seeking inspiration.
'We've got to reach the Control Centre.'
       The Doctor's darting gaze lighted on the Matter Transmitter
Couch. He smiled at his companions. 'Now that little gadget can be
made to go backwards.'
       Rogin shook his head. 'To reverse the polarities would take us
hours, Doctor,' he objected. 'There just is not time.'
       The Doctor tapped the side of his head. 'It so happens that I
have a few short-cut methods of my own,' he said, diving under the
control console of the Matter Transmitter.
       Rogin looked round unhappily at the others. 'But if there
should be the slightest error...' he began.
       'Take your choice,' came the Doctor's muffled interruption. '...
If this little trick fails, we shall either be gobbled up by the Wirrrn, or
dispersed particle by particle into infinity. And I know which of the
two fates I should prefer,' he added, re-emerging from beneath the
console and touching a switch.
       The transparent shroud covering the couch slid smoothly aside.
The Doctor motioned Rogin to climb on to it. 'After you,' he smiled.
With a moment's hesitation and a reluctant nod of assent from Vira,
Rogin gripped his laser gun firmly and lay down on the couch. The
shroud slid shut. The Doctor pressed a series of switches; Rogin
faded to a ghostly outline and then disappeared. Harry's eyes were
almost popping out of his head.
        'You next, Harry,' said the Doctor. In a daze Harry obeyed. He
too faded and disappeared. As Sarah took her turn, the Doctor
muttered confidentially to her, 'Sarah, I'm so relieved—I was not at
all sure it would work.'
        Sarah smiled nervously. 'Here I go again,' she called as the
shroud closed over her.
        The Doctor operated the switches; Sarah became a ghost for a
moment and then returned to flesh and blood reality. Through the
transparent shroud she grimaced at the Doctor. He smiled
apologetically and tried again. Sarah faded a second time and
instantly reappeared.
        At the same moment, the lights in the Access Chamber
flickered and sank to a mere glimmer. Rogin's voice crackled feebly
over the intercom from the Control Centre. 'Commander, we have a
power fade in Section Three.'
        Vira pointed to a warning display on a nearby console. 'The
Oxygen System has ceased operation,' she murmured.
        The Doctor beat his fists together in frustration. 'We're so
helpless in here,' he cried. 'If we could only dispose of Noah we
might have a chance of tackling the larvae while they are still in the
chrysalis stage—assuming that they are by now.' He glanced up at
the vents. An urgent tapping reminded him that Sarah was still
trapped in the Matter Transmitter Couch at his side.
        'Obviously I'm not going anywhere,' she scowled as the Doctor
released her. 'Where are you going though?' she demanded as the
Doctor suddenly whirled round and made for the Access Tunnel.
        'I shan't be long,' he called. 'Lock the door behind me—and
don't let anyone or anything in.'
        'Doctor,' Sarah shouted vainly after him, 'Noah is out there and
you...'
        But he was gone.

       Every nerve taut, his senses as sharp as those of a wild beast
stalking its prey, the Doctor sped through the dark, empty tunnels. At
any moment he might encounter Noah or the larvae, and he had no
weapon with which to defend himself. Although Sarah and Vira were
armed with the paralysator and with a laser lance, he knew they were
in terrible danger every moment he was away from the Access
Chamber.
        He soon reached the Radiation Shield leading into the Solar
Chamber. The shattered helmet belonging to Noah's protective suit
still lay where it had fallen. With great care the Doctor opened the
Shield and stepped warily into the Solar Chamber. At first he thought
the chamber was deserted. He was about to switch on the torch to
make sure, when he suddenly noticed that clinging to the softly
glowing reservoirs of the upper Ievels were huge, ovoid crystalline
objects. 'The pupal stage...' he breathed, peering up into the gloom.
Every fibre alert, he advanced up the steel ladder to the first level of
reservoirs. The Wirrrn pupae were transparent—like huge lumps of
clouded glass—inside which the skeletal form of the adult Wirrrn
was clearly visible, pulsating rhythmically like a heartbeat.
        Stealthily the Doctor approached the broad centre shaft which
contained the Solar Chamber systems controls and displays. He
found the Section Three panel open, its interior totally wrecked. He
set to work to try and salvage the oxygen supply circuits, at the same
time forming in his mind a scheme to electrify the Solar Chamber
and thus prevent the adult Wirrrn from breaking out once they
reached the imago stage. An occasional sharp splitting sound came
from the massed pupae above him, and the chamber was filled with
subdued rustlings and movements as the Wirrrn chrysali absorbed
energy from the globes.
        A shrill rattle, like the sound of a giant cicada, made the
Doctor spin round. A Wirrrn hovered over him, scraps of radiation
suit still clinging to its body.
        'Noah,' gasped the Doctor, pressing himself against the
exposed circuits. The eerie rattling was made by the rows of scythe-
like hairs rubbing together. The Wirrrn turned first one, then the
other of its huge eyes towards him. Then, with a sudden contortion of
its segmented body, it brought its tail up and over its head so that the
murderous claw hung above the Doctor like the sting of a giant
scorpion. The shrill rattling reached a climax as the claw opened. The
creature seemed to purr with triumph, uttering its own name.
'Wirrrrrrrrrrrrrrrn...'
       The vicious claw swung down at the Doctor's throat.
       Suddenly a series of deep lines was scored across the
underbelly of the rearing Wirrrn. It turned from the Doctor to face
the attack. From somewhere below him, the Doctor heard Sarah
screaming. 'Run, Doctor. Run...' He threw himself between the
creature's razor-bristling legs and rolled across the steel landing. He
glimpsed the terrified faces of Sarah and Vira in the torch-beam.
They were pointing the paralysator and the laser lance uncertainly
into the half-light. The Doctor dived down the companionway.
       'Get out. Out. Both of you,' he roared. 'The radiation in here
could kill you.' Reaching them, and grabbing them by the arms, he
steered them towards the open Shield and safety.
       'Stay, Vira, stay...' The words seemed to come from the depths
of the chamber itself rather than from the hideous apparition before
them. Vira twisted free from the Doctor's grasp and turned, letting go
the laser lance which fell clattering into the darkness below them.
       'Noah... Commander...' Vira cried, her voice choked with tears.
       The Wirrrn moved gradually closer to them, its legs rustling
like dry leaves against the metal struts. It stopped a few metres away,
crouched on the edge of the gantry above them.
       'Abandon the Satellite now... Take the Transport Vessel... If
you remain you will perish with the Sleepers....' The hushed whisper
enfolded them like a breeze. It was just recognisably the voice of
Noah, but it issued from the huge quivering mandibles of the giant
insect looming over them.
       Vira tried to approach a step nearer, but the Doctor held her
firmly back. 'We cannot abandon the Terra Nova. You know that,'
she murmured.
       The creature reared up again, its tentacles bristling. 'The
Wirrrn must survive... When we emerge the humans will be
destroyed—just as they destroyed us...'
       'What does he mean?' whispered Sarah.
       Noah reached out over them with quivering tentacles. 'Humans
came to Andromeda... For long ages the Wirrrn fought them... But
they destroyed our breeding colonies on Andromeda Gamma
Epsilon...'
       Vira turned to the Doctor with shining eyes. 'Then our stellar
pioneers succeeded,' she whispered.
       '... Since that time the Wirrrn have searched the Emptiness for
new breeding places... Now we have found an ideal habitat... The
Satellite is ours...'
       The Doctor edged forward a little. 'The Wirrrn inhabit the
Emptiness,' he said quietly. 'They do not need the Satellite.' Noah
was poised over them like a gigantic preying mantis.
       'You know nothing,' he rasped. Our breeding is terrestrial—we
require hosts for our hatchings... We shall use the humans in the
Cryogenic Chamber... In one generation the Wirrrn will become an
advanced technological species... We shall...' A sharp splitting sound
obliterated the rest of Noah's words. The Doctor eased the two
women slowly back towards the entrance.
       'The pupae are beginning to open,' he muttered. 'It's time we
were leaving.'
       As he spoke there came a fusillade of splitting sounds in rapid
succession. The Wirrrn's head moved slowly from side to side,
staring at them with fathomless, glowing eyes. Its claw swung in the
darkness above them. 'Leave the Satellite, Vira... Leave now...'
       Vira tried to resist the Doctor's guiding hand. 'Noah... Noah,'
she faltered.
       A shattering crescendo of cracks like gunfire made the Doctor
whirl round and thrust Sarah and Vira out into the tunnel. He closed
the Shield manually, and whipping out the sonic screwdriver,
directed it at the locking panel for a few seconds. 'That should
scramble the works,' he said. 'They'll have to chew their way out
now.' Then he led his two companions into the pitch darkness of the
labyrinthine Satellite...

      Harry stared down at the Matter Transmitter Couch in the
Control Centre where, for the past ten minutes, he had expected the
others to materialise just as he and Rogin had done. 'Something's
gone wrong with this gadget,' he said gloomily.
       Rogin grunted. He was busy working on a set of systems
panels he had lifted out from the wall. He had succeeded in restoring
the lighting in the Control Chambers although it was not very bright.
       Harry was irritated by the Technop's apparent lack of concern.
'Well, I do think we ought at least to investigate,' he said.
       Rogin pointed out that there was no lighting elsewhere in the
Terra Nova. 'After what happened to Lycett,' he added, 'I want to see
where I am treading.'
       Harry glanced down at his own shoeless feet. 'You should
worry,' he muttered.
       'Still no oxygen,' said Rogin, shaking his head. He stood up,
and as he did so seemed to jump a little from the floor and to be
suspended for a fraction of a second in the air. At the same moment,
Harry realised that the laser lance he was holding appeared to have
become mysteriously lighter. Before he could remark on it, there
came a sudden clatter from the adjacent Control Chamber, where the
TARDIS had materialised. Rogin grabbed the lance from Harry and
concealed himself to one side of the opening into the neighbouring
chamber. Harry leaped to the other side, bouncing lightly across the
floor.
       'Anyone at home?' The Doctor's hat was poked through the
open panel and waved about on the end of the telescopic probe.
       'Where on earth have you all been?' cried Harry as the Doctor
entered, followed by Sarah and Vira.
       'We bumped into Noah,' Sarah said wryly.
       'Excellent work, Rogin,' the Doctor said approvingly. 'You've
managed to shed a little bit of light on our problems.'
       'I have diverted power from the Gravity Static Field, Doctor,'
explained Rogin.
       'I thought I was feeling rather light-headed,' Sarah joked half-
heartedly. Rogin explained that he had not been able to restore the
oxygen systems. Vira hurried over to the Cryogenic Systems Monitor
Panel. The Doctor perched on the edge of the Transmitter Couch and
silently offered round the bag of melted jelly-babies. No one
responded. He sat deep in thought.
       The silence soon became unbearable.
        'Perhaps we should take Noah's advice,' said Sarah.
        'And what was that?' Harry asked.
        'Vamoose, or stick around and be killed,' she replied.
        Harry at once moved towards the entrance. 'Well I'm certainly
ready to get going,' he said eagerly. 'Why don't we all jump into the
TARDIS?'
        'Vira has no intention of abandoning her people, and neither
have we,' the Doctor snapped.
        Sarah moved over to join Harry. 'So that settles us,' she sighed.
'We'll just stay here and suffocate, or freeze or be gobbled up.'
        With a cry of frustration the Doctor leaped up. 'If we only had
a power source we could electrify the bulkheads of the Cryogenic
Section... The Wirrrn would never get through,' he said. '... There
must be a way—even with Noah in control of the Solar Chamber.'
        At that moment, Sarah remembered something. 'Just a minute,'
she cried, 'Noah said...'
        Harry interrupted her. 'Perhaps we could lure Noah out of the
Infrastructure and into a trap,' he suggested.
        'What do you have in mind, Harry?' the Doctor asked cuttingly.
'... a concealed trench covered with elephant grass?'
        Sarah tried to gain their attention. 'Doctor, listen, I've just
remembered...'
        The Doctor held up his hand for silence. He turned to Rogin.
'Could we confuse the Wirrrn by altering the Gravity Static Field?' he
asked.
        The Technop shook his head. 'It would take hours to trace the
lines of force,' he objected. The Doctor nodded in professional
agreement.
        'Will someone please listen to me?' Sarah had climbed up on to
the couch and was waving her arms frantically in the air. The Doctor
rounded on her with barely concealed annoyance.
        'What is it, Sarah?' he demanded sharply.
        'Noah mentioned a Transporter Vessel,' she replied. They all
looked blankly at her. 'Well, presumably it has a power system of its
own...'
      The Doctor clutched at his head. 'Why didn't you mention this
before?' he cried. 'I can't be expected to think of everything, you
know,' he added with a grieved expression.
      Harry helped Sarah down from the couch. 'Well done, old girl,'
he grinned.
      The Doctor rubbed his hands together with renewed spirit. He
asked Rogin how to reach the Transport Vessel. Rogin leaned across
and activated a large display-plan of the entire Satellite. He indicated
a shortened 'spoke' leading from the Cincture Structure towards the
central Infrastructure or 'hub', and ending halfway in a circular
Docking Structure where the Transport Vessel was mounted. The
Doctor studied the display closely.
      'We would have to run 'cables halfway round the Cincture
Structure from the Transport Vessel to the Cryogenic Chamber,' he
murmured doubtfully. 'The Wirrrn will simply cut them.' Rogin
nodded. The Doctor leaned closer to the illuminated plan. 'What are
those?' He indicated a complex of shafts and lattice girders joining
the Transporter Dock to the Central Hub where the Cryogenic
Section was housed.
      Rogin shrugged. 'Obsolete structures,' he said. 'Relics of the
time when the Satellite was functioning as a research base for stellar
exploration.'
      The Doctor peered through his magnifying glass. 'They
connect the Transporter Dock with the Cryogenic Section,'. he said
excitedly.
      'It is possible,'. agreed Rogin. 'But we would require a
mechanical cable-runner; the conduits are only forty centimetres
square.'
      There was a silence. Vira crossed the chamber from the
Cryogenic Systems Panel. 'We must do something soon,' she
murmured.
      'Couldn't I take the cable through?' suggested Sarah. 'I don't
take up much room.'
      'That's no job for you, Sarah,' Harry said firmly. Sarah flushed
with indignation. 'Now look here, Doctor Sullivan...' she began.
       The Doctor held out a length of his scarf in front of him, and
moving his hands apart, he counted off the coloured stripes. 'There:
forty centimetres,' he said, looking earnestly at Sarah.'... Do you
think you could crawl through a'shaft only this wide?'
       Sarah looked at the short length of scarf stretched between the
Dctttor's hands, and then glanced round at the others with a cool,
determined air. If she was having second thoughts she was certainly
not going to admit it. 'Of course I could,' she declared firmly. The
Doctor was full of admiration for her courage, but he looked worried.
He explained that there would be very little air or heat in the shafts,
and that Sarah would have no shielding against cosmic radiation
from Space. He also warned her that there would probably be many
dead-ends and confusing junctions.
       There was a short silence. Harry was looking apprehensively at
Sarah and shaking his head. That was enough for Sarah; she thrust
her chin defiantly forward. 'Well, what are we waiting for?' she cried.
'We'd better get started at once.'
       The Doctor hesitated a moment, then he patted her shoulder
and nodded. 'Splendid, Miss Smith,' he said. 'At last—an assignment
worthy of your talents...'
       They swiftly made their way from the Control Centre to the
great wheel-shaped Cincture Structure, the Doctor's torch playing
eerily over the polished walls of the tunnels. Everywhere was dark,
silent and airless. The immobilised shutters were opened by means of
small electronic master keys carried by Rogin and Vira. The curved
gallery of the Cincture Structure was dimly lit by the glimmering
stars shining through the observation portals. In every shadowed
alcove and corner they expected to find the Wirrrn waiting for them;
but the Satellite appeared deserted. Here and there the torch picked
out the silver tracks of the Wirrrn larvae, and Sarah shuddered when
they came upon blackened scraps of Noah's protective suit littering
the gallery floor.
       When they reached the junction with the Cryogenic Access
Tunnel, the Doctor parted company with the others. Giving the
thumbs-up sign to Sarah, he entered the Decontamination Airlock. 'It
shouldn't take me long to wire up the Cryogenic Chamber,' he
whispered. 'I'll be ready by the time you bring the cable through,
Sarah. Good luck, everyone.' The Doctor waved, and disappeared.
       Rogin led Sarah, Harry and Vira further on round the Cincture
Structure towards the Transporter Dock Access Tunnel... They all
knew that Sarah was about to risk her life in an appallingly
dangerous mission. Sarah herself knew that for a journalist it was the
scoop of a lifetime; but above all else in her mind was the realisation
that the future of the entire human race might now depend upon her
success...
                             7
                      A Tight Squeeze
       In the centre of the Solar Chamber hovered Noah, awaiting the
final metamorphosis of the Wirrrn creatures. The chamber was
seething with nightmarish activity as the pupae began to split asunder
to allow the emergence of the fully developed Wirrrn. First, the
transparent crystalline pods became clouded and opaque as billions
of tiny fissures burst through the brittle, resinous tissue. Then the
pods began to disintegrate and flake apart as the creatures within
pushed their tentacles through, sawing their way out with the sharp,
bristling hairs. Unearthly shrieks and whistlings echoed round the
chamber as the adult Wirrrn struggled to shed their crumbling pupal
form. In the midst of the upheaval Noah was poised, with raised
antennae, to establish himself as swarm leader...

       Rogin and his party reached the Dock Section safely. They
entered, through a complex of airlocks, into a dish-shaped area about
thirty metres across. Enormous bell-shaped nozzles hung overhead,
and the cradle supporting the Transport Vessel enclosed the humans
in a thicket of light steel struts. The Transporter itself towered
invisibly above them. Rogin at once began to clamber up one of the
support struts towards a small maintenance hatch set in the underside
of the Transporter. He carried one end of a heavy high-tension cable
from a vast coil that he and Harry had manhandled from an
equipment bay.
       Vira led Sarah over to a series of small sealed openings in the
side of the 'dish' area. She opened several of them with the electronic
master key, and directed a powerful microlamp into the dark
conduits. 'This one might be possible.' She motioned Sarah to look.
The shaft was just sufficiently wide to accommodate Sarah's hunched
shoulders.
       'It's awfully narrow, old girl,' muttered Harry; peering into the
icy darkness. '... If you take a wrong turning, I doubt whether you'll
be able to turn back.'
       Sarah smiled bravely. 'Then I'll just have to make sure that I
don't, won't I?'
       Vira helped Sarah to fit a tiny two-way communicator,
designed rather like a hearing aid with micro-phone attached, into her
ear. Harry unravelled the other end of the cable that Rogin was busy
connecting into the Transporter's generators, and secured it tightly
round Sarah's waist with a complicated nautical knot.
       'Well, it would be an awful bore if it came undone,' he said, as
Sarah tugged frantically at the loop of cable to gain a little room to
breathe.
       'Let's hope it's long enough,' she gasped. Vira quickly
explained to Sarah how she would be guided through the conduits by
radio from the Transporter Control Deck. She clasped Sarah's hand in
a brief gesture of good luck and clambered up to join Rogin in the
Transporter Vessel...
       When all was ready, Harry assisted Sarah as she squeezed
herself into the conduit, and began to pay out the cable as she inched
her way into the darkness. After a few metres, the cable stopped
moving. Harry poked his head into the narrow opening. 'How are you
doing, Sarah?' he called.
       '... 've harly go starhed yet...' came the muffled reply.
       'Sorry, old girl. I thought you were stuck,' Harry shouted. At
once the cable was jerked sharply out of his hands. Harry smiled to
himself.
       'Jolly good luck, old thing,' he murmured.

       In the Cryogenic Chamber the Doctor was well advanced with
the task of welding cable terminals to the wall sections of the huge
vault. All around him, the sleeping survivors of a terrestrial
catastrophe lay suspended between life and death, the delicate
Revivification systems starved of vital power, and the threat of the
rapidly developing Wirrrn hanging over them. If Sarah succeeded in
reaching the Cryogenic Chamber with the power cable, then there
was a good chance of not only preventing the Wirrrn from invading
the chamber, but also of restoring power to the chamber's vital
systems.
       Suddenly the Doctor switched off the torch and thrust the sonic
screwdriver back into his pocket. He stood quite still, barely
breathing, listening intently. There was a faint, dry rustling sound;
then silence. He peered into the darkness. In the direction of the
Access Chamber he saw two huge, ochre globes swinging from side
to side: the eyes of a Wirrrn. He backed stealthily away until he felt
the outline of a pallet behind him. Without taking his eyes from the
baleful stare of the creature he opened the shield. To his relief he
found that the pallet was empty. He climbed inside and closed the
shield. He lay motionless, straining his eyes to see through the thick;
distorting material...
       The Wirrrn moved slowly round the perimeter of the chamber,
apparently pausing to examine some of the pallets. Eventually it
approached and stopped in front of the Doctor, turning first one and
then the other eye towards him. The Doctor started, just managing to
suppress a cry, as something rattled and scraped against the pallet
shield. He blinked the sweat out of his eyes, and fought against the
painful cramp caused by his keeping utterly still in such an awkward
posture. The Wirrrn seemed to stare in at him for an eternity, its
sharp spines scratching against the shield with a noise that set his
teeth on edge. Then abruptly it turned away, and crawled across the
chamber towards the remains of the Wirrrn Queen. The Doctor
pressed his face against the pallet shield. He could just make out the
faint image of the Wirrrn's eyes as the creature whirled in a frenzy
away from the huge corpse of its progenitor, and disappeared whence
it had come.
       The Doctor waited for a few minutes, then quietly raised the
shield and climbed out of the pallet...

      As Harry clambered laboriously into the Control Module of the
Transporter, he overheard Rogin speaking quietly to Vira. '...
everything is perfect, Commander. We could depart for Earth now.
There is nothing to stop us...'
       'I say, just a minute...' said Harry suspiciously, easing himself
up into the small, cramped chamber. Rogin and Vira were seated in
moving, padded chairs which slid along and revolved around a slim
steel pillar running the length of the cylindrical chamber, thus
allowing the occupants to reach all parts of the control panelling.
       'Generator Manual Overrides linked, Commander,' announced
Rogin, completely ignoring Harry. 'Initiation of Primary Phasing in
forty-five seconds from now.'
       At that moment, Sarah's voice burst loudly over the intercom.
'Hello, Rogin. I've reached what feels like a three way junction... it's
very tight...'
       Rogin traced his finger over an illuminated plan of the conduit
structure on the video-screen before him. 'You are making good
progress,' he replied. 'You must now proceed to the left.' There was a
short silence, broken by the sound of Sarah's struggling efforts.
       'I can... I can hardly move at all...' she suddenly panted. There
was the sound of a brief tussle, and then Sarah's frightened whisper.
'I think the cable is caught. somehow...'
       Vira swung angrily round on Harry. 'You should not have left
the conduit hatch,' she said icily. 'The cable is obstructed.'
       Harry shamefacedly Scrambled back down the alloy ladder,
and descended swiftly to the Docking Area.

       Inside the conduit, Sarah was drenched in perspiration despite
the intense coldness which numbed her fingers. She had to fight for
every breath. Her knees and elbows were raw from scraping against
the sides of the narrow shafts. Her hair repeatedly caught itself
between her shoulders and the metal sides of the conduits, forcing
her to continually retreat a few centimetres in order to release it. The
smooth sides afforded her nothing to grip on. She could move only
with a kind of caterpillar action which was terribly exhausting; she
contracted her body, pressed her knees against the shaft and then
straightened her body, pressed her elbows outwards and finally drew
her legs along after her by contracting her body. She had to repeat
this awkward sequence over and over again. She was often close to
despair as the cable snagged, or the bulky knot which Harry had tied
jammed itself between her hip and the side of the shaft.
        Now she was twisting this way and that in a frantic attempt to
free the cable; but it refused to budge, and the more Sarah wriggled,
the tighter she became stuck. Tears of frustration welled up in her
eyes. Her skin seemed to adhere to the cold metal shaft, and would
only come away with a sharp and painful wrench. She could see
absolutely nothing. She gasped for oxygen. She could move neither
forwards nor backwards. 'It's just no good...' she sobbed. 'I'm sorry, I
can't do anything to...'
        All at once she felt the cable tugging. For a horrifying moment
she thought that something was in the shaft with her, and trying to
drag her back towards itself. She had a fleeting vision of the Wirrrn
larvae bubbling up through the shaft and engulfing her in a searing,
suffocating mass. Then she realised that the jerking of the cable
formed a regular pattern; it seemed like a morse code message! After
a few minutes concentration she deciphered it: 'COME ON OLD
GIRL... YOU CAN DO IT.' Instantly Sarah's energy increased a
hundredfold. 'Patronising male chauvinist,' she muttered through
clenched teeth, visualising Harry's anxious face at the other end of
the conduit.
        With a supreme effort she eased herself forward a few
centimetres. To her amazement and joy the cable did not resist.
'Just... you wait... till I get out...' she panted.
        'Please repeat your last message,' requested Rogin's puzzled
voice over the communicator.
        Sarah heaved herself forward. 'Message cancelled,' she replied.
At once she was confronted by a bewildering array of shafts
branching off in all directions. Even following Rogin's careful
instructions, it was almost impossible to orientate oneself in the pitch
darkness. Sarah knew that if she took a wrong tunnel, or came to a
dead end, she had no chance of making her way back again.
        A faint glimmer of light ahead spurred her on. 'I can see light,'
she whispered excitedly into the tiny microphone.
        'Yes,' came Rogin's encouraging reply. 'You are entering an
old Hydrodynamics System. It runs right through the Solar
Chamber—move as quietly as you can.' To her horror, Sarah found
that the conduit had become tubular in section, and even narrower
than before. She now had to stretch out her arms ahead of her, and to
move forward by turning her whole body like a corkscrew. She
ceased to be aware of her badly grazed elbows and knees, of the
burning sensation in her lungs, but forced herself onward through the
tube. Her painfully slow progress was further hampered by her legs
becoming inextricably tangled with the cable as she rotated her body.
       She soon found herself in a section constructed of translucent
material. Her pounding heart missed a beat as she recognised,
through the thick glass-like material, the subdued glow of the Solar
Chamber. Rogin's voice came whispering through the earpiece; it
seemed to come from the other side of the universe. 'Quietly now,
Sarah...'
       She froze as, from the depths of the Solar Chamber, there
loomed two enormous eyes. Helplessly Sarah stared back at the
Wirrrn crawling towards her, its gigantic mandibles working
hungrily. The creature gripped the tube with its tentacles. In vain
Sarah tried to flinch away from the slashing, razor hairs as they
squeaked against the conduit only centimetres from her body.
       The Wirrrn tried to take the tube between its mandibles. Sarah
could see right into the dark red pulsing throat of the giant insect.
She felt violently sick. Rogin's voice came urgently over the
communicator. 'Sarah... what is happening... are you safe?'
       The inside of the tube had steamed up so that Sarah could no
longer see her attacker, but only hear the shrill scrape of its tentacles,
and feel the shuddering of the tube as the Wirrrn tried to crush it. She
marvelled at the extraordinary strength of the unfamiliar glassy
substance which was all that kept her from the jaws of the creature.
She felt like a fly trapped in a blob of amber which could at any
moment be smashed to smithereens with a hammer.
       She collected her wits, and frantically twisted herself along the
tube. The Wirrrn followed, angrily wrenching at the conduit, its eyes
burning at her through the tubing and its massive jaws completely
enclosing her struggling body. Sarah glimpsed more and more of the
fierce glowing eyes clustering around her as she fought her way
through the final section of the Solar Chamber... She imagined
herself crawling through the bowels of some prodigious mythical
beast.
       To her relief, the tube suddenly reverted to metal sections. She
welcomed the darkness with its feeling of security, but she could not
be sure that the Wirrrn would not eventually manage to shatter the
'glass' section and sever the vital cable—or even drag her backwards
into the Solar Chamber again.
       'Is... is it much further... ?' she implored, her imagination
conjuring an endless maze of dark, stifling tunnels in which she was
condemned to crawl for ever.
       'You are almost there... another fifteen metres,' came Rogin's
welcome reply.
       'I do hope so...' Sarah gasped,:.. because I don't think I can go
on much longer.'
       .'Stick at it, old girl,' came Harry's cheerful voice.
       'That's just the trouble,' Sarah snapped back. 'I keep getting
stuck.' Then she managed a smile to herself as she visualised Vira's
and Rogin's blank stares on hearing her little joke.

      The Doctor had almost completed his preparations in the
Cryogenic Chamber. For the moment, the Wirrrn seemed to be
leaving him in peace, deterred perhaps by the discovery of the corpse
of the Queen. Nevertheless, the Doctor remained fully alert as he
crouched in the darkness, sonic-welding cables from the wall
terminals into a large junction box by torch-light. From time to time,
he crossed to the central shaft and listened for signs of Sarah's
progress. It was nearly an hour since he had bid her good luck in the
Cincture Structure. He knew that it could not be very long before the
Wirrrn in the Solar Chamber reached imago form in overwhelming
numbers, and returned to the attack.
      There was a hollow, distant panting sound which suddenly
reverberated in the central shaft. The Doctor raced across the
chamber into the elevator cubicle where the Wirrrn Queen had been
hidden, and put his car to the side of the shaft.
        'Sarah...' he murmured. He tapped rhythmically and then
listened. His tapping was repeated beat for beat. 'Sarah... Hurry,
Sarah... hurry,' he called, shining his torch up into the darkness.
Ducts and conduits ran into the shaft at right angles as far as the
Doctor could see. He directed the torch-beam at each aperture in
turn. 'Can you see anything, my dear?' he said. There was a pause,
then Sarah's faint reply.
        'No... not. yet. I'm now in some kind of coiled section, Doctor.
I'm not sure I can get round the bends...'
        'Of course you can, Sarah,' encouraged the Doctor, keeping a
wary eye on the dark vault of the Cryogenic Chamber. 'You've got
this far...'
        'But, Doctor, I'm completely stuck this time,' Sarah
'whimpered. '... I seem to be glued to the sides.' The tall shaft rang
with Sarah's sobs of frustration and fear. 'Doctor, I'm... I'm upside
down... and I feel very very faint....'
        The Doctor stared upwards, his face full of anxiety. They were
so close to succeeding. Sarah could not fail now. He cupped his
hands to his mouth and bellowed as loudly as he could up into the
shadows. 'That's right... blubber away, Sarah... just what I expected
of you.'
        There was a brief pause, then Sarah protested tearfully, 'But,
Doctor, .I am completely jammed. I can't go up or down.'
        'Oh, stop whining, girl,' retorted the Doctor brutally. 'You are
utterly useless.'
        There was a shocked silence. 'Doctor,' Sarah's voice came
through at last. 'Doctor, how can you...'
        But the Doctor showed no remorse. Instead of apologising he
went on, 'It was a mistake to rely on you in the first place .. Harry
was quite right—It was no job for a girl...'
        Sarah had heard enough. She wrenched herself round and
round inside the tortuous spiralling tube in a frenzy, oblivious of
pain, fear or discomfort. 'You wait... I'll show you...' she gasped.
        The Doctor was smiling broadly to himself, delighted that his
little ruse had worked so well. 'The future of Mankind at stake, and
all you can do is lie there blubbering,' he called as a final goad to
Sarah's temper.
       But Sarah was no longer listening. Within a few minutes her
head appeared out of one of the ducts high up in the shaft wall. In the
torchlight the Doctor could see that her hair was matted and her face
streaked with tears, but her smile was triumphant.
       The Doctor grinned up at her. 'Splendid, Sarah. I knew you
would do it,' he whispered.
       Sarah peered down at him in amazement, dazzled by the torch.
Then she smiled again. 'You are a brute,' she laughed, despite her
exhaustion. 'You conned me completely.'
       'Just trying to encourage you, my dear, that's all,' the Doctor
murmured innocently. He shone the torch around the sides of the
shaft. Sarah was stranded a good thirty metres above him. 'Now all
we have to do is get you down,' he said.
       'Oh, please don't worry about me. I'll just jump,' retorted Sarah.
'As long as you get the cable down safely I'm sure I hardly matter.'
       The Doctor swept the, torch round the cubicle. 'If we had any
power I could fetch you down in the lift,' he said.
       There came a sharp rattling sound from the Access Chamber.
Instantly the Doctor began working away with the two lengths of his
scarf. Sarah could not see what he was doing, but she gasped in
astonishment and admiration when, after a few seconds, he flashed
the torch quickly over the giant 'cat's cradle' he had fashioned across
the bottom of the shaft, using the framework of the open elevator
cubicle on which to secure the scarf-ends.
       'Jump, Sarah, jump,' the' Doctor hissed.
       Without pausing to think, Sarah obeyed and leaped into the
dark abyss. She landed in the safety-net the Doctor had improvised.
A pair of strong hands came out of the darkness and lifted her gently
but quickly down.
       'Harry's tied the Gordian Knot here all right,' whispered the
Doctor, feverishly trying to undo the cable from around Sarah's
waist.
       Over the Doctor's shoulder, Sarah suddenly noticed the
unmistakable glow of a Wirrrn's eyes on the far side of the Cryogenic
Chamber. Only minutes earlier she had been struggling between the
jaws of one of the fearsome creatures inside the conduit. A violent
shudder shook her body and she thrust her fingers into her mouth to
stifle a scream. At the same moment, the Doctor freed the cable.
Something was pushed into her free hand. It was the torch. 'Try to
distract it, Sarah,' murmured the Doctor, moving stealthily away
from her with the cable.
       'What... ?' she gasped. But. there was no time to protest.
       She switched on the torch and shone the beam up over her face
from under her chin, transforming her features into a macabre mask
suspended in mid-air. She felt the Doctor detach the communicator
set from around her head.
       'Splendid idea,' prompted his voice in her ear. 'But whatever
you do, keep away from the walls.'
       Sarah began to sidestep away from the Doctor, her eyes fixed
firmly on those of the Wirrrn. The huge, ochre globes swung steadily
towards her; she could hear the heavy, leathery body dragging itself
across the chamber floor as she backed away from it. Still very dazed
from her ordeal inside the conduit system, Sarah struggled to
visualise the exact shape of the Cryogenic Chamber so that she
would not back into any of the walls; she knew that hundreds of
thousands of volts would surge through them when Rogin switched
on the power. She could just make out the Doctor's whispered
instructions to Rogin through the communicator. Counting her
faltering steps, Sarah knew she must be very close to the chamber
wall. Still the Wirrrn bore down upon her.
       Suddenly, to her left, she heard the Doctor whistling as if he
were calling a dog. 'Here... Here, boy...' he coaxed. The Wirrrn's eyes
turned away from her and began moving towards the sounds. The
Doctor fell silent, and the Wirrrn hesitated. Then it resumed its
pursuit of Sarah. She switched off the torch, darted a few steps to the
right in the pitch darkness, then crouched quite still, holding her
breath. Again the Wirrrn stopped. Its eyes began to glow a bright
fierce orange. The menacing rattle sounded. Sarah found herself
mesmerised as the Wirrrn's eyes swung hypnotically before her. She
could feel it tantalising her. Then her blood ran cold as she heard
what sounded-like sharp intakes of breath which rapidly grew into a
rhythmic roaring, like the sound of a gigantic bellows. The creature
was sniffing her out...
       The Doctor whistled again, this time from her right. The
Wirrrn hovered uncertainly a moment, then moved swiftly towards
the invisible figure.
       'Torch, Sarah. Torch,' screamed the Doctor. Sarah switched on
the torch and waved it recklessly about. The Wirrrn swooped towards
her. She crept backwards, step by step, shining the torch-beam
directly into the creature's eyes. With a rattle of triumph the Wirrrn
reared up over her. She froze as something crumpled against the
backs of her legs. She dropped the torch and toppled backwards into
the disintegrated corpse of the Wirrrn Queen... At the same instant
she heard the Doctor shouting into the communicator. 'Now, Rogin.
Now.'
       A blinding blue-white flash lit up the Cryogenic Chamber.
Sarah glimpsed the huge pincer slicing down at her. There was an
ear-splitting shriek, and the sound of a massive body thrashing about
in agony. Something soft and rubbery brushed across Sarah's face. A
sickly burning smell filled the darkness. She lay among the rotting
tentacles of the Wirrrn Queen shivering with nausea and choking
from the acrid fumes. Then came the sound of the crippled Wirrrn
crawling slowly away from her, and moaning with a croaking,
gurgling cry which reverberated around the chamber until it died
away into silence. As it gradually faded, the comforting gentle
humming of the Cryogenic Systems resumed and the familiar faint
glowing reappeared in the pallets. All around her the Chamber came
back to life. Sarah closed her eyes in relief but before she could haul
herself to her feet, she suddenly felt extremely dizzy. She keeled over
on her side in a dead faint just as the Doctor reached her...
                            8
                     A New Beginning
       In the Flight Control Module of the Transporter Vessel, the
tension was becoming unbearable. Harry, Rogin and Vira waited
anxiously for news from the Cryogenic Chamber. Sarah's piercing
cries and the bizarre shrieks of the Wirrrn still rang vividly in their
ears. Harry was hunched over the communicator set calling again and
again. 'Doctor... Sarah... are you all right? Come in please... Doctor,
can you hear me...?' But there was no reply, only a relentless silence.
Vira kept watch on the Launch Area through the video scanner,
while Rogin, grim-faced, monitored the Transporter's generator
systems.
       'We cannot maintain this level of power indefinitely,
Commander,' he warned.
       As if in reply, the Doctor's voice suddenly came through on the
communicator. 'Rogin, whatever happens don't let the power fade.
We've won the first round... and I've managed to feed some energy
into the Cryogenic Systems, but there's very little to spare...'
       'You have done well, Doctor,' interposed Vira.
       'Thank you,' came the Doctor's reply. 'But if the Wirrrn should
detect our power source, you could be in grave danger. You had
better electrify the Launch Dock.'
       Rogin interrupted to explain that such a plan was impossible
since the Transporter Vessel was moored to the Satellite by Synestic
Locks.
       'How very inconvenient, Rogin,' came the Doctor's
disappointed voice. 'I should have realised: if you energise the
Docking Area you may reverse the Synestic Fields and push the
Transporter Ship out into Space.'
       'Exactly, Doctor,' murmured Rogin.
       There was a short silence. The Doctor spoke slowly and
pointedly over the intercom. 'Well, you ought to think of something,
Rogin, before the Wirrrn think of you...' The communicator went
dead again. Harry tried to re-establish contact, but without success.
      Rogin turned to Vira, his face filled with dismay. 'Commander,
I shall soon be forced to reduce power... our generators will be
needed for the transfer to Earth... we cannot risk a malfunction.' Vira
nodded gravely.
      Harry sensed a certain irresolution in the manner of his two
companions. 'Don't forget,' he warned. 'If the Wirrrn should get into
the Cryogenic Chamber there won't be any transfer to Earth.'

       In the Cryogenic Chamber, Sarah sat propped against the
elevator shaft, recovering from her ordeal. She had regained
consciousness to find herself wrapped in the Doctor's voluminous
jacket, and the Doctor bending anxiously over her. She was still
shivering with cold, and beginning to notice the effect of the oxygen
system being shut down. She kept a wary eye on the opening into the
Access Chamber, just visible in the restored glow of the pallets,
while the Doctor bustled about the chamber checking his circuits
leading from the junction box. One set was feeding power into the
pallet Revivification Systems, while the other supplied the
improvised 'electric fence' around the lower section of the chamber
walls, and also the trailing cable with which the Doctor had fought
off the Wirrrn attacker.
       'Not bad for a lash-up, eh?' he grinned. 'But I hope the
insulation will stand it,' he added, gesturing round at the pallets on
floor level which were still occupied by dormant humans.
       Sarah nodded towards the Access Chamber. 'The Wirrrn know
where we are now,' she whispered, clutching the Doctor's jacket
closer to herself for warmth.
       The Doctor waved the torch about under his chin. 'You pulled
such faces,' he chuckled in an effort to reassure Sarah. 'I don't think
the Wirrrn, will be in a hurry to come back...'
       Without warning the Access Chamber was flooded with light.
Sarah shielded her eyes against the intense glare which temporarily
obliterated her view of the entrance. 'Why have they turned the
power back on?' she cried. The Doctor shrugged. Still carrying the
free-running cable, he advanced towards the Access Chamber,
motioning Sarah to stay where she was. Just as he reached the
entrance, a distorted gabbling suddenly burst out all around them.
For a second Sarah imagined that the sleeping humans in the
Cryogenic Chamber had suddenly revived, and that they were
shouting in unison at her in a language she did not understand. She
rushed to the Doctor's side in terror.
       They stood in the Access Chamber listening to the eerie
cacophony echoing around them. It was punctuated by harsh squeaks
and hoarse whistlings. Gradually, there emerged a ghostly whisper,
the shadow of Noah's human voice. 'Vira... Vira... hear me...'
       The Doctor indicated to Sarah to keep quiet, and went over to
the intercom panel set into one of the Access Chamber systems
consoles. He flicked the talkback button. 'What do you want, Noah?'
he called.
       A hostile buzzing issued from the intercom. Through it rose
Noah's hollow whispering. 'Your resistance is useless. We control the
Satellite.' The vicious buzzing increased as if in approval of Noah's
words.
       'And we control the Cryogenic Section,' said the Doctor
defiantly. 'I repeat, what do you want?'
       'Go now... your lives will be spared,' came Noah's blurred
reply.
       'Impossible,' shouted the Doctor contemptuously.
       The babble of Wirrrn voices reached a crescendo of furious
anger. Noah's words struggled to be heard. 'Let... Vira... speak... She
is Commander...'
       The Doctor waited a moment, then he said, 'Vira is occupied
with the revivification of her people.'
       The boning of the Wirrrn reached a deafening roar. Again
Noah's voice rose above. it, this time filled with scorn for the
Doctor's attempted bluff. ''That cannot be; the systems are isolated.'
       The Doctor gave an exaggerated laugh. 'You forget, Noah, I
have quite a way with electronics.'
       'You lie,' Noah screamed, his voice breaking into monstrous
gasps and screeching sounds.. 'I am the Swarm Leader... I guarantee
your safety... if you leave the Sleepers for us.' The Doctor said
nothing. The Wirrrn gradually fell silent, then Noah hissed, 'If you
refuse... we will suffocate you.'
       Sarah stared at the Doctor with frightened eyes. She
remembered only too well the terrible sensation of breathlessness
when the TARDIS had first materialised in the Satellite's Control
Centre, and also during her ordeal inside the conduits. The Doctor
gazed at the intercom panel, his face filled not with anger or hate, but
with a kind of infinite weariness. He closed his eyes, racking his
brains for some stratagem with which to defeat the Wirrrn. After a
long pause, during which the angry murmurs from the Solar
Chamber began to rise again, he started to speak very quietly, in a
last appeal to Noah..
       'Noah... please listen to me... if there remains within you any
trace of your humanity—if you have any memory of the human you
once were... leave the Terra Nova... lead, your swarm into Space—
that is where the Wirrrn belong... not on Earth... Earth is for the
humans... Do you remember the Earth, Noah?... the wind... the sea...
the sky... dawn and sunset...'
       Noah broke in with a prolonged sighing voice which sounded
through the chambers long after the intercom went dead. 'I... have...
no memory of... the Earth...'

       In the Transporter Control Module, Harry had begun to fear
the worst. There had been no contact with the Doctor since his
warning about a Wirrrn attack on the Docking Sector, and he was
also anxious for news of Sarah after her heroic success in reaching
the Cryogenic Chamber. He was staring gloomily at the video
scanner, wishing there were some simple way of returning to his
office at UNIT Headquarters and forgetting all about Satellites and
giant locusts and travelling Police Boxes.
       Suddenly he leaned forward to look more closely at the
fluorescent screen. 'I say, Rogin,' he murmured. 'I don't want to be an
alarmist, but there's 'something moving out there.'
       Rogin swung round and adjusted the scanner. A blurred,
moving shape came into focus; three Wirrrn were crawling across the
Docking Area towards the struts leading up to the Transporter's open
maintenance hatch. At once Rogin manoeuvred himself over to the
Propulsion Unit Panel. He began to operate a series of keys,
muttering mechanically to himself. 'Particle Emission Phase:
initiated...' A colourful illuminated scale began to register on the
panel. 'Acceleration to Tachyon Phase... Negative Thrust... Go.' The
Transporter was enveloped in a piercing whine. It vibrated and
shuddered at its anchorage. 'The Synestic Locking Field is holding,'
Rogin called above the din.
        All at once, the view of the Docking Area on the scanner was
obliterated by a brilliant blue glare. After a few seconds, Rogin shut
down the Propulsion Unit. The incandescent glare faded gradually
away, revealing in the centre of the Docking Section a shapeless blob
of colourless matter like melted glass. It was the fused remains of the
three Wirrrn.
        'Good show, Rogin,' cried Harry. 'That singed their whiskers!'
        Vira sat staring blankly at the massive crystal shimmering
beneath the Transporter. 'I wonder if Noah...' she began, then she
lapsed into silence.
        'Commander?' Rogin inquired gently.
        Vira immediately recovered herself. 'It is of no importance,'
she said firmly.
        'Are you all right over there?' The Doctor's voice boomed over
the communicator.
        'Doctor!' said Harry. 'Yes, we're fine, thanks. Nice to hear from
you at last.' Harry quickly explained what had happened..
        'They're up to something clever,' the Doctor muttered grimly.
'... For some reason they've restored the power here...'
        A series of warning lights flickered in front of Rogin. He
leaned over and adjusted the scanner so that it showed the outside of
the Transporter hull, and the great silver shape of the Terra Nova
turning slowly against the multitude of stars...
        Floating eerily from around the outside of the Solar Chamber
there came a cluster of Wirrrn. As they drifted into view, they linked
their tentacles together, forming a chain which snaked its way slowly
across towards the Transport Vessel. The Wirrrn looked like giant
sea creatures, feeling their way through the deep.
        Harry spoke rapidly into the communicator. 'Doctor, the
Wirrrn have broken out of the Solar Chamber. They are approaching
us. It looks as if the whole swarm is going to attack.'
        Rogin glanced across at Vira. 'Commander, if the Wirrrn break
into the hull we shall be lost. The internal bulkheads have a low
stress tolerance...'
        On the scanner, the Wirrrn leader could be seen feeling with its
antennae for a suitable gripping point on the hull of the Transporter
Vessel.
        'Have you all gone to sleep?' shouted the Doctor. 'Rogin, cut
the power. We're coming out.' Rogin obeyed. They heard the Doctor
conferring with Sarah, then he added, 'Rogin, if the Transporter has
an Automatic Flight System then initiate it at once, and evacuate the
ship.'
        Vira turned to Rogin in shocked protest. 'I forbid this. If we
sacrifice the Transport Vessel we have no hope of returning to
Earth...'
        Rogin said nothing, but pointed to the scanner screen. The
Wirrrn leader had now secured itself to the Transporter hull; one by
one the creatures clambered over the 'bridge' formed by the others.
The Wirrrn were soon swarming all over the hull. A sickening
tearing sound rang through the Ship; warning lights flickered on the
panel in front of Rogin. 'The Wirrrn have pierced the hull in the
Stabiliser Unit, Commander,' he cried. 'The sealing shutters are
operating.'
        Rogin frantically began to programme the Transporter for
Automatic Launch in accordance with the Doctor's instructions. He
did not understand the Doctor's intention, but he had come to trust
and respect the shambling, eccentric stranger.
        Harry manipulated the scanner, panning down towards the
Transporter Propulsion Unit. What he saw sent shivers along his
spine—a huge Wirrrn was tearing through the hull with its pincer as
easily as a plough cutting a furrow in the soil. It was rapidly ripping a
hole large enough for itself to enter. The whine of the Ship's
generators, the shrill scrambling of the Wirrrn and the shriek of
tearing metal combined into a deafening cacophony. More warnings
suddenly appeared on the panels as the internal bulkheads began to
yield.
       'The Wirrrn have entered the Transport Vessel,' Rogin shouted,
pushing Harry towards the hatch in the floor of the Control Module.
'You have four minutes to leave the Ship and clear the Launch Area
before the Dock Shield opens and the Dock de-pressurizes to
vacuum.' Harry nodded and followed Vira down the alloy ladder. All
around them, the Transporter resounded with the Wirrrn's onslaught
as they clambered hastily down the servicing tunnels, desperately
making for the maintenance hatch before the Wirrrn could penetrate
into the bowels of the Vessel. At any moment, a giant pincer might
slice through a bulkhead, or a panel might open to reveal a rearing
Wirrrn, its claw poised in triumph, barring their escape.
       They reached the maintenance hatch safely and Rogin caught
up with them as they slid down. the struts to the Launch Deck. At the
same moment, the Doctor and Sarah emerged from the airlock and
they all met beneath the gigantic propulsion nozzles, where the
twisted remains of the three Wirrrn lay like a vast glass sculpture.
The Doctor gestured to Harry to escort Sarah and Vira back through
the air-locks into the main Satellite. Harry tried to object to deserting
the Doctor and Rogin at such a vital moment, but the Doctor pushed
him firmly away. Soon Harry and the two women were making their
way cautiously towards the Control Centre where the TARDIS stood
patiently waiting. To their amazement and relief they did not
encounter any Wirrrn as they crept through the chambers' and tunnels
of the Satellite.
       With the Transporter's motors thundering above their heads as
the Tachyon Drive prepared to 'go critical', Rogin and the Doctor
each ran to one of the main anchorage struts beneath the propulsion
nozzles. Rogin pointed to the chronometer bracelet on his wrist, and
then held up two fingers. The Doctor nodded and brandished the
sonic screwdriver; Rogin nodded and held up his synestic key. They
both immediately set to work to release the Synestic locks—three in
number—on the main struts. Having completed the first one, Rogin
glanced at his wrist. The chronometer scale showed barely a minute
remaining before the huge circular shield, a hundred metres above
them, opened like the 'iris' in a camera, allowing the atmosphere
inside the Launch Area to evacuate into Space.
       The Doctor had also completed the release of his synestic
anchorage. They both made for the third and final lock, and arrived
at the strut together. The Doctor motioned Rogin to take refuge in the
safety of the airlocks. Rogin shook his head and bent down to deal
with the remaining magnetic clamp. 'Get into the airlock, man,' the
Doctor screamed in Rogin's ear. '... There's no sense in us both being
disintegrated.' He tried to pull Rogin away from the strut. With a
sudden lightning movement, Rogin stood up, catching the Doctor
neatly on the chin with his head. The Doctor slumped heavily on to
the deck.
       Rogin dragged him across to the airlock and dumped him
inside. He closed the outer shutter and ran back to the third synestic
lock. On his chronometer bracelet the red arc showed just five
seconds to zero. As Rogin released the last clamp, he was enveloped
in a deathly chill: the air was sucked out of his lungs, and the blood
began to boil in his veins as the Docking Section de-pressurized. Far
above him, the elegant 'iris' shield was opening to allow the
Transporter to launch itself into Space. He crumpled with a soundless
scream...
       A few moments later, the Launch Area was filled with a
searing plasma discharge. Rogin's body was transformed into a
shapeless and colourless crystal in microseconds. Almost
imperceptibly at first, the huge Transport Vessel separated from the
Launch Assembly and began to climb away from the Docking Area.
The very gradual acceleration was designed to disturb the Satellite's
orbit as little as possible.

      In the Control. Centre, Sarah, Harry and Vira—watching on
the main scanner—felt the slightest jolt. They stared in silence as the
Transport Ship moved slowly away from the Terra Nova. Of the
swarming Wirrrn there was no trace. The massive, ovoid craft began
to accelerate into the depths of Space, its Tachyon Propulsion System
leaving a brilliant blue aura in its wake. It grew smaller and smaller,
finally becoming indistinguishable among the myriad stars. The
luminous 'comet' tail lingered a little longer, then it too faded into
nothing.
       At last, Vira spoke. 'The Doctor and Technop Rogin must have
perished instantly.' Sarah turned away from the scanner, stifling the
sobs that rose in her throat. Harry moved over to her side, and put his
arm gently round her shoulders.
       'Come on now, old girl,' he said. 'You know he'd have wanted
you to be brave.'
       Sarah shook her head. 'It's such a waste,' she murmured.
       'Not if it means that Vira's people are saved,' said Harry
consolingly. 'I think we've seen the last of the Wirrrn.'
       But Sarah was overwhelmed; she looked up at Harry, her eyes
brimming with tears. 'Harry, I just can't believe it... I just can't.'
       'What can't you believe, Sarah?' boomed a familiar voice. The
Doctor was standing in the entrance to the neighbouring Control
Chamber, massaging his bruised chin. They were all too stunned to
move or speak. The Doctor walked sadly across to Vira. He took her
gently by the arm. 'Rogin is dead,' he said.
       'He sacrificed himself so that the Satellite would be saved.'
Vira nodded and turned slowly away towards the Cryogenic Systems
Monitor Panel.
       Sarah at last found her voice. 'Doctor... how did you escape... ?'
       'Thanks to, Rogin's bravery—and perhaps also to something
else... The Doctor's words tailed off as he turned to stare at the
scanner screen where the Transporter had disappeared among the
stars.
       'Something else, Doctor?' asked Harry, puzzled.
       The Doctor walked over to the scanner. 'Yes, Harry. Some
vestige of the indomitable human spirit, perhaps.' He turned to face
them. 'Was Noah one move ahead of us all the tune... and even of the
Wirrrn at the end... ?'
       Vira looked at. the Doctor in astonishment. 'You mean that
Noah deliberately led the Swarm into the Transporter?'
       The Doctor smiled and nodded. 'I took a gamble that he would,
and that...'
       The Doctor was interrupted by a rapid bleeping; an indicator
pulsed on the External Communications Panel. Vira stared at it for a
moment, then hurried over and touched a switch. 'Project Terra
Nova... The Commander,' she said crisply, identifying herself. Above
the faint mush of static they gradually distinguished the distant
murmur of the Wirrrn Swarm. A single, clearly human voice
emerged and softly filled the Control Chamber.
       'Farewell... Farewell, Vira...'
       Vira stretched her arms out towards the scanner. She struggled
to speak, but could not. Her arms fell back to her sides, and she stood
motionless. All at once, one of the billions of tiny points of light
flickering on the screen flared up like a supernova. For a moment it
blazed, then it disappeared into nothingness.
       'The Transport Ship's exploded,' Harry gasped. The Doctor
walked thoughtfully away a few paces and then looked back at the
scanner.
       'Infinite Mass,' he muttered to himself. 'Noah had absorbed all
Dune's technical knowledge. He must have known that would
happen. He deliberately neglected to activate the plasma stabilisers.'
       Sarah looked at the Doctor in amazement. 'You mean Noah
sacrificed the Wirrrn for our sakes?' she cried.
       Vira spoke with firm emphasis. 'Noah sacrificed himself for the
sake of his people here,' she said.
       The Doctor nodded and smiled at her. 'Now you can at last
begin the great awakening of your people,' he said. But Vira shook
her head. She was contemplating the Cryogenic Systems Monitor
Panel which indicated that the initiation of the Main Revivification
Phase was imminent.
       'It is too late,' she murmured. 'Without the Transport Ship we
have no means of reaching Earth.' The Doctor frowned. He glanced
irritably at Sarah and Harry, as if this latest difficulty were their fault.
Vira moved towards the panel, her hand raised, as if she were about
to cancel the Revivification Process once and for all, and abandon
the great plan which had succeeded thus far against incalculable
odds.
       The Doctor rushed forward and seized Vira's arm.
       'Wait,' he cried. 'The Terra Nova Project will still be fulfilled.
You can use the Matter Transmitter to reach Earth.'
       Again Vira shook her head. 'There is no receiver on Earth. It is
an internal system only.'
       The Doctor put his hands on Vira's shoulders and looked
earnestly into her eyes. 'If you and your people will trust me,' he said,
'I can go down to Earth and fix something up for you. With a little bit
of juggling at this end we should be able to make it all work.' Vira
stared at the Doctor as if he were demented. 'Oh, I realise that you'll
have to travel one at a time,' he shrugged. 'And of course it will
require enormous power; but I am sure that your Solar Power
engineers will be able to oblige,' he added with a smile.
       Vira opened her mouth to object, but the Doctor broke in
briskly, with a gesture towards the Cryogenic Systems Panel. 'Look,'
he cried. 'It's almost "reveille". We must make a start.'
       Everyone followed the Doctor as he strode into the adjacent
Control Chamber. Vira stared open-mouthed as the Doctor unlocked
the door of the TARDIS. 'Old faithful,' he murmured affectionately,
patting the chipped and faded blue paintwork.
       Vira gasped in disbelief. 'Do you ask me to accept that you are
intending to convey yourself to Earth... by means of this... this
obsolete artefact?'
       The Doctor looked grieved. He rubbed his finger across the
dirty frosted-glass panes in the door, and grimaced at the blackened
skin. 'This,' he said proudly, 'is a vintage specimen of Time And
Relative Dimensions In Space technology—TARDIS—and, far from
being obsolete, it has not even been invented yet.'
       The Doctor adjusted his charred hat to a jaunty angle, and
turned to step into the TARDIS. He collided with Harry who, hands
firmly thrust into his pockets to avoid the temptation to tamper with
anything, was about to enter with Sarah.
       'Where do you two think you are going?' he demanded.
       'Oh, you're bound to need a helping hand down there, Doctor,'
Sarah laughed. 'You always do....'
       Harry smiled apologetically. 'The Brigadier did ask me to keep
an eye on you, Doctor,' he said.
       The Doctor frowned, then he motioned them inside. 'Very
well, just this once,' he agreed grudgingly. 'But you'd better both put
some warm things on—one never knows what the weather's going to
be like.' Sarah and Harry disappeared eagerly inside.
       The Doctor turned to Vira. 'We shouldn't be very long,' he said.
       'I shall expect you... soon,' replied Vira. 'Meanwhile I must
return to the Cryogenic Chamber. The Main Phase is beginning.'
       Sarah and Harry reappeared in the doorway of the TARDIS,
clad in waterproofs and wellington boots.
       'Back soon,' cried the Doctor, waving the jelly-baby bag. He
broke off a piece from the melted contents and threw the bag to Vira.
'Good luck,' he called.
       Vira caught the bag neatly. 'Good... luck... ?' she repeated the
unfamiliar phrase to herself, puzzled.
       An extraordinary groaning sound made her look up. A bright
yellow light was flashing on top of the strange blue box into which
the Doctor and his companions had entered... As she watched, the
box faded and gradually disappeared.
       Suddenly Vira smiled in recognition. 'Yes... yes,' .she cried.
'Good luck...'
       She tentatively broke off a small piece from the sticky lump in
the bag and put it into her mouth. She grimaced, then she smiled and
nodded in approval at the taste. She looked at the empty space where
the TARDIS had stood. 'Good luck, Doctor... and thank you,' she
murmured.
       She turned and left. In the Cryogenic Chamber, her people
were awakening in their hundreds. At last her task had begun...