'We all panic sometimes,' Ian said gallantly, though inside he was feeling frightened and angry.

The next section was much more difficult. Ian had to stretch his body almost horizontally across the chasm and lever himself upwards with his hands behind his back and his feet flat against the opposite side, gradually straightening his legs as the funnel widened out.

Vicki clasped her arms around his waist and did her best to ease the strain by using her own feet as best she could, but the weight on Ian's back and legs was almost unbearable. Several times he lost his grip and they slipped back a little way down the treacherous shaft.

Eventually, after an agonising struggle, they reached the top. Ian was just able to span the gaping hole without his body buckling in half and sending them slithering to the bottom again. He told Vicki to pull herself along his legs until she could grab the edge of the hole by his feet and drag herself up onto the ramp. At last she managed to clamber out of the hole and she hurried round to kneel behind Ian's head. Reaching down, she slipped her hands under his arms.

'Whatever you do don't let go!' he warned, gripping her hands with the insides of his arms. 'Now pull!' While Vicki supported his body, Ian swung his legs down and dug his heels into the side of the shaft. With a furious back-pedalling movement he manoeuvred himself up onto the ramp. Vicki gave him a grateful hug and they sat side by side on the edge of the hole breathlessly marvelling at their amazing good luck.

Seconds later a piercing scream brought them scrambling to their feet.

'Barbara!' Ian gasped. He grabbed Vicki's hand and led the way up the ramp in the direction of the anguished cry.

Suddenly Vicki stopped. 'What is that noise?' she whispered.

They listened. Something huge was approaching along the ramp, dragging itself in short spasmodic heaves. Ian put his hand over Vicki's mouth and pulled her into a deep recess in the rock. They waited in silence, hardly daring to breathe. The ma.s.sive thing came closer and closer and soon they could hear a sort of shrill snuffling sound. In the faint light from the veins of luminous rock, they saw a glistening spherical head looming towards them, tiny red eyes burning on either side of the slimy featureless ball.

Behind the head, a thick segmented body looped and curled and slid itself forward by bunching up and then expanding its elongated armoured rings. The gigantic worm was at least fifteen metres long.

'What is it?' Vicki eventually whispered once the monster had pa.s.sed.

'Some kind of arthropod I suppose,' Ian replied, watching as the huge head suddenly disappeared into the ground. 'And I think we've just been trespa.s.sing on its front doorstep.'

Vicki shuddered. 'You mean we...' It was too horrible to even think about.

'Yes, Vicki. We've had a miraculous escape. I think that thing lives down the hole.'

'But surely it couldn't fit,' Vicki objected.

Ian thought a moment. 'Perhaps when it emerges it leaves a lot of debris behind like a sort of plug,' he suggested vaguely.

They listed to the sound of furious burrowing from the hole.

'That might explain the bones,' Vicki murmured.

'Bones?'

'As you said, when it comes out of the hole it probably brings up... well, debris.'

Ian put his arm round Vicki's shoulder as much to comfort himself as to rea.s.sure her. 'Not a very hospitable planet to land on!' he murmured wryly. 'What with that thing and Sandy and Koquillion and silver robots. Come on, let's go and find...'

'Barbara!' they chorused, turning to each other in dismay. In the horrifying encounter with the giant armoured worm they had temporarily forgotten all about the scream and their missing companion.

Barbara crouched in the alcove, pressed against the immovable shutter that had trapped her on the ramp. She was still shaking with terror and nausea after her close encounter with the hideous worm. She had been so scared that she had scarcely been able to bring herself to look as it slithered past her cramped refuge. It was a long time before she could bear to open her eyes and convince herself that it really had gone.

Very slowly she ventured out of the alcove and listened to the monster's receding movements. When they had ceased altogether she thought she heard distant voices echoing faintly in the tunnel from the same direction. It took all her willpower to resist the temptation to call out Ian and Vicki's names. As she crept tentatively down the slope she felt the sticky trail of the giant worm clutching at the soles of her shoes with a sound like spitting fat in a pan and it was all she could do to stop herself retching in disgust.

She paused again, listening for the ghostly voices. But there was nothing but menacing silence all around her.

Growing a little bolder, Barbara continued on down the ramp. She began to wonder what kind of function it might have had in the Didonian settlement which seemed to stretch right into the heart of the mountain.

A sudden scuffling behind her made her quicken her pace. The scuffling seemed to come closer and closer and she broke into a run, heedless of the hazardous darkness. A cry of panic burst from her lips as she put a foot into yawning empty s.p.a.ce and found herself toppling forward.

At the same instant, both her arms were seized and she was yanked backwards so that she fell flat on her back screaming hysterically. Pale faces loomed over her.

'Barbara! It's all right! It's only us!' Ian's voice hissed gently over her as friendly hands helped her to her feet again. 'You nearly fell into the hole!'

11.

A split second before Bennett's murderous talons slashed into his throat the Doctor glimpsed the sonic laser device hanging at the side of the c.u.mbersome Koquillion attire.

Grabbing it from its magnetic clasp, the Doctor flung the heavy instrument into his attacker's face.

Bennett screamed with pain as the ring of hard crystal lenses cut into his flesh. Staggering back, he crashed into a display cabinet which cracked open like an egg showering him with fragments of gla.s.sy material. The Doctor dived forward to seize the sonic laser which had skidded across the polished stone floor under one of the neighbouring cabinets.

But he was not quite fast enough. Wrenching off the awkward talons, Bennett freed his hands and beat the Doctor to it. He raised the lethal device and aimed it at the Doctor at pointblank range, fiddling frenziedly with the small control b.u.t.tons on its handle.

'You haven't a chance,' Bennett gasped, wiping the blood out of his eyes. 'This thing can pulverise your insides faster than a microwave beam.'

The Doctor racked his brain for some desperate evasive move while Bennett tried to activate the laser device which seemed to have been damaged by the Doctor's throw.

'You'll just end up as a squashy skin bag full of jelly...'

Bennett laughed, managing to switch on the primer circuit with his big clumsy fingers.

Suddenly the Doctor remembered something. Fishing frantically in the voluminous cluttered pockets of his frock coat he unearthed a small bra.s.s-mounted concave mirror, a relic from an antique microscope he had once tried to restore. As Bennett pressed the trigger b.u.t.ton the Doctor held up the mirror and directed it at the device. The air whined with a stream of high-pitched rapid pulses and a thin beam of bluish light shot out of each of the crystal lenses arranged around the disc at the end of the barrel of the mechanism. The Doctor's thick mirror reflected the beams back again, focusing them into a single intense spot at the centre of the disc.

The Doctor struggled to stand his ground and steady the mirror as it violently throbbed and vibrated in his hands, almost forcing him over onto his back. With a shrill splitting sound the laser machine shook itself to pieces in Bennett's numbed fingers, clattering to the floor in a shower of disintegrating components. Dumbfounded, Bennett stared at his empty tingling hands and at the fragments of his super-weapon scattered around him.

The Doctor grinned and flourished the hot mirror triumphantly. 'I always think wet shaving is so much less hazardous, Mr Bennett!' he quipped, blowing on his scorched fingers.

Bennett simply stared at him incredulously, shaking his head in silence as if he were in the presence of a legendary magician.

'Like vampires, people who fire laser guns shouldn't look in mirrors,' the Doctor chuckled, pocketing the lucky talisman.

Slowly Bennett pulled himself together. Without taking his cold grey eyes off the Doctor for one second, he struggled out of the heavy Koquillion outfit and extracted his feet from the huge talons which had enc.u.mbered his movements so disastrously. Then he advanced on the Doctor, his thin lips frothing like the mouth of a crazed dog.

The Doctor quickly realised that in spite of his slight injury from the crashlanding of Astra Nine Astra Nine, Bennett was far more agile than he had pretended to be for the purpose of deceiving Vicki. As Bennett raised his huge hairy hands in a strangling gesture, the Doctor ran back around the altar looking anxiously for some means of escape or self defence.

Suddenly Bennett changed direction and almost caught the old man as he abruptly reversed his retreat and fled round the other way.

Bennett smiled contemptuously. 'You may as well give up old man,' he jeered. 'Why not make it all much easier for both of us? Stay where you are and let me finish off this unpleasant little business with the minimum of fuss.'

Just then the Doctor caught sight of the torch lying where it had been kicked in the previous scuffle against the base of the altar. Playing for time, he gave a conciliatory smile. 'Mr Bennett, do you spell your name with one "t" or two?' he inquired calmly.

'What possible significance could that have for you?'

The Doctor shrugged and edged very slowly round towards the torch. 'Oh, I just wondered whether you were related to the great Bennet, the cosmological engineer,' he said casually trying to hook the torch towards him with his toe. 'You have have heard of the Bennet Oscillator of course?' heard of the Bennet Oscillator of course?'

Bennett hesitated, uncertain how to react to this.

'No? Oh well, perhaps it hasn't been invented yet,' the Doctor said, dragging the torch nearer. 'A beautifully simple but highly effective device.'

'You are quite mad!' Bennett breathed, starting to advance slowly round the altar.

The Doctor jack-knifed at the waist, picked up the torch and straightened up again. Switching on the torch, he was relieved to find that it was still functioning. He flashed the powerful beam into Bennett's eyes.

'It works!' he cried. 'Or rather it will when it has been invented, on the principle of photon inertia using a small array of multiply vectored lasers,' he babbled on, backing away towards the huge pillars leading to the entrance. 'I do hope I'm not blinding you with science, Mr Bennett?'

Bennett shouted out in frustration, shielding his eyes from the brutal glare as he tried to pursue the retreating figure of the Doctor.

'I refuse to believe that there is not at least some some good in everybody,' the Doctor continued, talking nineteen to the dozen. 'So who knows? Perhaps one of your distant descendents will give the world the Bennet Oscillator. Let us hope so.' good in everybody,' the Doctor continued, talking nineteen to the dozen. 'So who knows? Perhaps one of your distant descendents will give the world the Bennet Oscillator. Let us hope so.'

'I have no children!' Bennett spat with savage scorn. 'It would be madness to bring new life onto a doomed and poisoned Earth. I am not prepared to do it!'

The Doctor felt his way around the first pillar. 'Most alturistic of you. But you are are prepared to take life away, it seems.' prepared to take life away, it seems.'

Bennett kicked the bulky Koquillion garb out of his way and the talons skidded across the floor squealing and hissing against the glazed slabs. 'What do you know about me?' he snapped between hard white teeth.

'You are a self-confessed murderer. You have even succeeded in misusing a peaceful tool developed by Didonian technologists as a weapon!' the Doctor retorted as Bennett's boots crunched over the remains of the sonic laser.

'I killed in self-defence,' Bennett protested.

'On which occasion?' the Doctor demanded sardonically, backing towards the next pillar nearer the entrance.

Bennett stopped. 'On the mission... Eight years cooped up with McQuade... He was high...

Deoxyphenylsulphonates... I caught him trying to alter the navigation programme... But I was too late... We were forced to divert here to Dido... It was McQuade...' Bennett clenched his huge hands and his big body shook with rage.

The Doctor paused, puzzled. 'Then if you were acting in defence of the Astra Nine Astra Nine and its personnel, why should you want to conceal McQuade's death by even more killings? It seems a curious method of defending people. and its personnel, why should you want to conceal McQuade's death by even more killings? It seems a curious method of defending people.

They perished anyway.'

Bennett rushed at the Doctor. 'I don't have to justify myself to you, you senile old fool!' he snarled savagely.

Taken by surprise, the Dpctor attempted to turn and flee but he was cornered against the pillar. He struck out at Bennett's crazed face with the torch, but next moment Bennett's powerful hands closed around his throat. 'Then why bother?' he gasped, his grip on the torch loosening and his arms lolling at his sides as Bennett's grip tightened.

'The others got in my way, just like you...' Bennett growled, his eyes goggling with hysterical pa.s.sion. 'Why do people always have to interfere?'

The Doctor wanted to reply that he had often asked himself exactly the same question, but he was unable to speak or even gasp, so tight was Bennett's crushing grip around his windpipe. His knees buckled and he slowly slid down the pillar, his face fixed in a purplish mask of mute desperation as he stared pop-eyed at his a.s.sailant. Bennett's face was frozen in a trancelike spasm of raw hatred as he squeezed the breath out of the feebly twitching busybody.

Gradually the Doctor's body went limp and hung in Bennett's hands like a bundle of old clothes in a jumble sale.

Bennett gazed blankly at his victim for a moment. Then his eyes filled with uncertainty and fear. His hands slackened around the Doctor's throat and he half-turned his head as he heard strange soft sounds behind him. With a hollow moan, the Doctor slumped onto his side at the base of the pillar and lay deathly still and silent. Bennett swung on his heel with a startled cry and then he began to back away, shaking his head and making odd little gibbering noises as he gaped in horror at something standing on the altar. 'No... no... no... You are all dead... I killed you all... You are all dead... !' he suddenly shrieked.

The tall silver figures had appeared on the altar as if from nowhere, like G.o.ds. Their lithe frames, more than two metres in height, shimmered in the shafts of coloured light reflected from the altar slabs. Their emerald eyes stared expressionlessly in Bennett's direction, but seemed to look right through him as if he did not exist. Their suits reflected the surroundings like mirrors and Bennett gazed at his own awestruck and terrified face frozen in the dazzling sheen of the material. It was as though the things had stolen his image, even his very ident.i.ty, and left him an empty sh.e.l.l.

Bennett glanced at the entrance. It was still closed and he had not heard the ear-splitting shriek of its hinges.

'How did you... get in here?' he stammered, breaking out in an icy sweat.

He tried to distinguish their features, but as always the things seemed to have none, the brightness of their silver suits somehow making their faces fade into insignificance except for the circular eyes which gave nothing away. 'Why don't you ever answer?' Bennett yelled, beating his fists together in frustration.

The figures continued to stare through him, silent and absolutely motionless.

Bennet was unnerved by their silence and he began to panic. 'I could help you...' he offered, in a pathetically submissive voice, taking a few hesitant steps towards the altar. 'Your civilisation is in ruins. I could work for you.

We could restore all the magnificence...'

Bennett's voice cracked into silence as the two figures suddenly moved forward and stepped down onto the floor, their slender limbs suggestive of enormous strength and suppleness.

Sweating and trembling, Bennett continued to gibber and gesticulate helplessly as he backed away from the inexorably advancing figures. Suddenly they separated, and by moving swiftly in opposite directions round the altar, trapped him in front of one of the thrones which formed the corners of the octagonal structure. Terrified out of his wits, the big man clambered up onto the stone seat still mouthing meaningless words and phrases at the silent relentless beings. Then he stepped up onto the central slab and moved slowly into the centre, as if he was steeling himself to make a break for it across the altar and up the length of the huge chamber to the stone door.

One of the figures put its silver gloved hand onto the arm of the throne. There was a sharp crack, like the sound of a whiplash, and the top of the altar snapped open like a huge black mouth. Bennett was suspended for a moment in mid air, like a character stepping off a cliff in a cartoon film. 'I killed you all... I killed you all all...' he croaked.

Then he vanished into the void, the sickening thump of his body against the sides of the shaft echoing time and time again, until at last it was swallowed up in darkness and silence.

With another whiplash crack the altar snapped shut.

The two silver figures turned abruptly and strode back to the pillar where the Doctor lay motionless and pale as chalk. Their eyes brilliant in the subdued light, the figures stooped over him and stretched out their jerkily clasping hands.

The Doctor's eyes flickered open for a moment and he stared dully at the two blurred things which kept merging and separating crazily in the air above him.

His mouth opened as if he was about to speak. Then it sagged shut and his eyes closed again, as though for the last time.

12.

The Seeker Seeker Mission was in serious trouble. In the navigation module First Deputy Weinberger and Trainee Oliphant sat shoulder to shoulder at the console trying to work out what was wrong. Mission was in serious trouble. In the navigation module First Deputy Weinberger and Trainee Oliphant sat shoulder to shoulder at the console trying to work out what was wrong.

'It cannot be the mach inertia system or the laser gyros,'

Oliphant reported, sitting back in his padded seat and rubbing his tired bloodshot eyes. 'They all check good.'

Weinberger nodded up at the incredibly detailed galactic neighbourhood chart shimmering on the wide curved screen above their heads. 'Beats me, son. There is no apparent malfunction anywhere, but we are fifty per cent further away from Dido than we should be and we were tracking thirteen microarcs off true course before we corrected.' The big American brushed his bristling crewcut and chewed his gum morosely. 'I surely would love to know what we encountered back there.'

Oliphant shrugged and tapped the miniature hologram plate beside him on the console. 'Freak reception perhaps.'