Vicki continued. 'As I told you, we left Earth in 2493. We were the ninth group of colonists to the planet Astra.'

'And what caused you to crash here?' Ian asked.

Vicki looked blank and aimless again. She shrugged and spread her hands. 'Some of the crew suspected sabotage. I have no idea what happened. All I remember is a horrible, sickening vibration. There was a radiation leak in the main core or something.' She shuddered. 'We were thrown off course and captured by Dido's gravitational field.'

'How long have you been stranded here?' Barbara asked gently.

'It seems like a whole lifetime.'

Ian moved to the interior hatch. 'Talking of time, the Doctor's taking rather a lot of it. What's he doing in there?'

Vicki looked sharply at him. 'We must not disturb them!' she snapped.

'I shan't disturb them. If they don't want to be interrupted, they only have to say so,' Ian replied casually, surprised at Vicki's outburst.

Ian clambered through the intermediate compartment and knocked on the partly open shutter. 'Doctor? Mr Bennett? Can I come in a minute?'

There was no reply.

Barbara and Vicki watched through the internal hatchway as Ian tried to force the shutter wider apart.

'Doctor? Mr Bennett?' he repeated.

Still there was no response.

A rough grating noise from inside Bennett's compartment filled Ian with alarm. 'Doctor? Are you all right in there?' he shouted, struggling to force his broad shoulders through the narrow gap. He stumbled inside and stared around him in amazement. 'They've disappeared!'

he called, scratching his head. 'They've gone! There's no sign of them at all.'

He spent several minutes searching the compartment for some clue as to where the Doctor and the mysterious Bennett might be. Baffled, he gave up and clambered back through the intermediate compartment and through the internal hatch. 'I don't understand it at all...' he said to Barbara and Vicki.

But he was talking to himself. Barbara and Vicki had vanished!

9.

Crouching low, the Doctor scuttled through the rocks past the huge motionless corpse of the silicodon and across the shallow crater towards the entrance to the low tunnel from which he and Ian had emerged earlier.

Although he had the torch in his pocket, he was grateful for the pale waxy light which Dido's three visible moons cast over the wasted planet since he was anxious not to give away his presence, at least for the moment.

He stopped among a thick tangle of thorn trees, threw back his head and listened intently to the weird sounds which filled the chill air. They were like the distant but bloodcurdling nocturnal moans of mysterious and unimaginable creatures. Although the Doctor scanned the craggy ridges, the deserted terraces and the surrounding plain, he could see nothing that might be responsible for the nightmarish sounds. Perhaps they came from within the planet itself-a kind of mourning lament for some lost Golden Age, the Doctor mused. He had not revealed all that he knew about the planet Dido to the others, and now he was hoping to discover whether his suspicions about Vicki's Mr Bennett were justified.

The Doctor ducked inside the dark tunnel and switched on his torch. He shone the beam along the ground and his gimlet eyes soon identified a faint trail of claw imprints leading up the broad beginning of the ledge which he and Ian had heroically followed along the side of the giant cavern.

'I don't think these these were left behind by any of poor Sandy's relations,' he muttered, kneeling down to inspect the prints more closely. His eyes lit up with particular interest when he also noticed some other vague footprints in addition to the claw prints. 'Peculiar shoes young Chesterton wears,' he murmured, turning his foot on its side and studying the sole of his boot for a moment. Then he examined the scuffed patterns in the layer of sand again and soon identified his own and Ian's prints in the form of a third trail overlapping with the others. 'I wonder who the second lot of prints belongs to?' the Doctor said thoughtfully as he got to his feet. 'Odd that we did not spot the trails before...' were left behind by any of poor Sandy's relations,' he muttered, kneeling down to inspect the prints more closely. His eyes lit up with particular interest when he also noticed some other vague footprints in addition to the claw prints. 'Peculiar shoes young Chesterton wears,' he murmured, turning his foot on its side and studying the sole of his boot for a moment. Then he examined the scuffed patterns in the layer of sand again and soon identified his own and Ian's prints in the form of a third trail overlapping with the others. 'I wonder who the second lot of prints belongs to?' the Doctor said thoughtfully as he got to his feet. 'Odd that we did not spot the trails before...'

He edged his way cautiously up the sloping ledge which began to narrow as it climbed along the cavern wall. Soon the torch picked out the ornamented panel. Grunting with satisfaction, the Doctor stuck his spectacles on the end of his nose and studied the hieroglyphs, prodding and poking the ancient characters with his finger in different sequences.

'Come along now, open Sesame...' he whispered, his mouth drawing down at the sides and his high forehead creasing with concentration. After several false tries his patience was rewarded with a series of soft clicks inside the rock and the panel slowly swung open, squealing on its dry hinges.

Taking off his spectacles the Doctor paused on the threshold for a moment, letting his eyes accustom themselves to the strange milky light. Then he entered the long, high, barrel-shaped chamber beyond the portal, advancing with slow cautious steps and delving into the deep shadows with his penetrating gaze. He started as the door suddenly swung shut behind him with a shrill squeal which echoed horribly for several seconds in the vast arched vault overhead.

The roof was supported on ma.s.sive tall columns which splayed out on the top like gigantic mushrooms. From the wide brims of the columns a subdued light radiated upwards bathing the vault with a pale opalescent glow; and from the rings of light, pastel-coloured vapours rose like the scent of exotic flowers, mingling to form a subtle rainbow effect of breathtaking beauty. As the Doctor walked slowly along the avenue of columns, he noticed that the carved rock surfaces of the chamber were veined with threads of iridescent crystals which reflected the variegated light like strings of countless miniature prisms.

In the centre of the chamber stood a ma.s.sive, low structure resembling an altar. Octagonal in shape, it was made of huge slabs of polished stone carefully cut so that the angled facets reflected the milky light from above in a tangle of subtle beams. The Doctor walked respectfully round it and then moved into the shadowy s.p.a.ces behind the columns where awesome carvings, masks and murals depicting ferocious beasts adorned the walls. Between the columns, there were enormous gla.s.s cabinets containing ceremonial robes, head-dresses and weapons belonging to some ancient civilisation of great richness and imagination. The whole chamber possessed a dramatic atmosphere of profound solemnity and ritual power.

As the Doctor wandered among the cabinets studying the artefacts on display, he tried to puzzle out what could have been the cause of the sudden change in the once peaceful character of the inhabitants of Dido. Something crunched under his boots. Glancing down he saw that he was walking on broken gla.s.s. The front panel of the next cabinet had been shattered and its contents removed. The Doctor switched on the torch and leaned through the huge jagged hole to inspect the mountings for the missing exhibits and the weird hieroglyphics on the indentification tags. Only one word of the ancient Didoi text meant anything to him.

' Khakhuiljan Khakhuiljan...' he whispered, giving the mysterious symbols their nearest equivalents in human speech. 'Our old friend Koquillion, unless I am very much mistaken.'

Putting on his spectacles again, he fretted over the other symbols for quite some time, but failed to make any sense out of them.

Eventually he gave up and returned to the huge central altar. 'Many generations of sacrificial victims...' he mused, running his hand along the worn edges of the polished slabs. Deep in tought, the Doctor sat down in one of the eight throne-like chairs elaborately carved out of the corners of the altar.

He settled himself as if expecting a long wait for someone or something and brooded over his suspicions, occasionally nodding his head with grim misgiving. 'And I have a nasty feeling that certain ancient rituals have recently been revived..

Ian stepped gingerly out through the external hatch and stood in the eerie light of the three moons. He peered around and listened for some trace of the missing girls.

The night was full of deep colossal shadows cast by the ma.s.sive structures of the wrecked s.p.a.ce craft and the air was filled with the distant unearthly sounds that the Doctor had heard. Listening to the bizarre noises, Ian began to imagine horrible visions of Barbara and Vicki being dragged helplessly away by unspeakable monsters to their mountain lairs. It seemed impossible that they could have vanished without trace in such a short s.p.a.ce of time.

Finally he plucked up courage and ventured out into the shadows around the hull. 'Barbara... Vicki... Are you there?' he called. The distant sounds seemed to mock him.

He jumped as something suddenly clanged against the side of one of the huge scorched cylinders forming the s.p.a.ce craft's tail section. Slowly he approached the ma.s.sive structure looming against the sky. It looked as big as a stadium. The thump of his heart against his ribs frightened him almost more than the fantastic shapes silhouetted against the moons.

Reaching one of the detached cylinders whose leaning black bulk rose out of the sand like a windowless tower block disturbed by an earthquake, Ian took a deep breath and felt his way cautiously into the yawning bell of metal at its base. 'Barbara? Vicki? Where are you?' he called. His voice echoed in the cavernous tubes and chambers in the darkness above him like an announcement of doom. He listened for a reply with fading hope, more and more convinced that something dreadful had befallen the two girls. Gradually he became aware of a low hoa.r.s.e breathing sound somewhere nearby. It made him think of huge leather lungs being worked by some sort of cybernetic mechanism, like a giant robot bellows. Crouching down, he felt around and picked up a stout metal bar. As he straightened up he heard another sharp metallic clang.

This time it seemed to come from one of the other detached cylinders standing some distance away.

Feeling a little more confident armed with the primitive weapon, Ian crept out of the tilted base of the cylinder and ran across the dry rutted ground to the nearest of the other broken-off cylinders a hundred metres or so away. As he edged round the curved skirt of the cylinder he recognised the strange drapery of gauzy foil hanging in the mouth of the structure. The drapery was twitching and flapping here and there even though there was no longer any breeze to disturb it. Cuffing the clammy sweat out of his eyes, Ian forced his feet to move his trembling body towards the sinister metal drapery. He froze as something scuttled and sc.r.a.ped in the distant shadows beneath the main structure.

He thought he glimpsed a momentary silvery flicker around the cylinder where he had heard the menacing breathing, but if there had been anything there it was no longer visible.

He thought of Prince Hamlet stabbing poor old Polonius behind the arras as he raised the metal bar above his head and prepared to advance on the shimmering chainlink curtain now barely a couple of metres away.

Trying to ignore his drumming heart, Ian took a few hesitant steps. Next moment, something grabbed his wrist, something else jabbed him in the groin and several voices including his own, burst out simultaneously: 'Got you!'

'Get away from me!'

'Look out!'

He was dragged through the rattling drapery and thrown sprawling onto the sand while two invisible figures jumped up and down on top of him in a frenzy.

'It's me!' he yelled.

There was a shocked silence.

'It's him! It's Ian!' Barbara's voice shouted.

With everybody talking at once, Ian was hauled to his feet and dragged back into the open. 'Come on, you two!'

Ian ordered. Quickly taking charge, he seized their hands and ran across the eerie landscape to the welcoming rectangle of light in the side of the hull. They scrambled inside and collapsed on the bunk, the table and the duct all pale and breathless and shaking.

'We thought... We thought you were the silver things...'

Vicki gasped, smiling with relief.

Ian looked startled. 'Silver things? What silver things?'

Barbara ma.s.saged her injured shoulder which had received another wrench in the tussle with Ian. 'While you were looking for the Doctor and Bennett... They came through there...' Barbara pointed to the internal hatchway.

'Who did?' Ian interrupted, totally confused.

'The two figures... They came through the wreckage in there... We tried to warn you but they... We ran out and hid in the big cylinder thing...' Barbara explained, panting for breath.

'One of the catalyser filters...' Vicki added helpfully.

Ian tried to organise his jumbled thoughts. 'I couldn't find the Doctor or Mr Bennett next door and when I came back in here you'd both disappeared too, so I looked for you. Then I heard this heavy breathing and I thought it was that Koquillion chap or whatever his name is...'

Barbara stood up, her bruised and grimy face tense with worry. 'But if the Doctor and Bennett aren't here, then where are they?' she murmured, going over to the internal hatch and gazing through the tangled wreckage at the dim light coming from the partly open shutter.

Vicki stood up, her face drawn and frightened.

'Perhaps... Perhaps Koquillion came...' she whispered.

Ian shook his head emphatically. 'Impossible, Vicki. We would've heard him or seen him. They would've called out.'

Barbara turned to Ian. 'Surely the Doctor wouldn't just go away without telling us?'

Ian grinned ruefully. 'Oh, I wouldn't put it past the old codger, especially if he's discovered something interesting.'

Barbara shrugged helplessly. 'Well, what do you suggest we do?'

'I think we should remain here,' Vicki advised earnestly.

'It is not safe to go outside at night.'

Ian thought for a moment and then stood up decisively.

'No, I vote we go back to the TARDIS. That's where the Doctor will make for eventually.'

Barbara glanced at the darkness beyond the external hatch. 'But what about those silver things and what about Koquillion?' she reminded them, reluctant to leave the light and the relative security of the Astra Nine Astra Nine.

'I cannot leave here without Bennett,' Vicki said in a submissive voice.

'Well, Bennett's jolly well gone and left without you,'

Ian pointed out cynically.

'But he can't walk properly,' Vicki protested. Her face suddenly hardened. 'I think that the Doctor has taken him away.'

Ian laughed in her face, frustrated by her objections and still a little frayed at the edges after his unnerving experience outside. 'Don't be ridiculous!' he scoffed. 'Can you really imagine the little old Doctor lugging a disabled fully-grown man out through a crack in the wall?'

Barbara grimaced at Ian to shut up and put her arm around Vicki's thin shoulders. 'Come with us, Vicki. You'll be much safer than you'd be staying here all alone,' she said earnestly.

Vicki hesitated, biting her lip in nervous indecision.

She glanced at Ian and he smiled and nodded encouragingly. 'All right,' Vicki agreed at last. 'But I must activate the locator beacon first, otherwise the Seeker Seeker might not find us. might not find us.

Ian watched impatiently while Vicki knelt by the communications lashup and switched on the radio signal that would guide the rescue mission to the exact spot. As the equipment came alive the drain on the feeble power cells caused the lights to fade to an even dimmer level. The compartment now looked much less inviting.

'I hope the power will last,' Vicki murmured gloomily.

'If the beacon fails we may be stranded here for ever.'

Impatient to be away, Ian took her by the shoulder.

'Come along, Vicki. Let's get back to the TARDIS,' he insisted.

The Doctor had almost dozed off once or twice despite the hardness of the stone seat. In spite of all the menacing and violent images of the huge masks and the vivid murals looming in the shadows, the vast ceremonial chamber exerted a hypnotic and dreamlike effect, and the Doctor had noticed that the colourful vapours rising into the vault above him were filling the air with a pungent sleepy haze, like incense in a cathedral. He had deliberately seated himself with his back to the entrance but in such a position as to enable him to see the dark doorway reflected in the gla.s.s front of one of the display cabinets. He could also see his own reflection, and in the pale overhead light his dark clothes, flowing white locks and severe profile gave him a quite terrifying aspect which made him jump the first time he noticed it! Indeed, he looked like the effigy of an ancient G.o.d sitting in judgement.

After what seemed like an eternity, even to the Doctor who was accustomed to insulating his senses from the frustration of pa.s.sing time, he heard a soft clicking noise behind him. Then the stone panel swung open on its shrieking hinges with a terrifying sound which echoed thunderously around the huge chamber.

After a pause, the Doctor heard an eerie hissing and wheezing sound and then an awkward scratching noise slowly came nearer and nearer. Squinting into the gla.s.s front of the cabinet, the Doctor made out a hideous spectral shape lurching up behind him between the pillars.

Koquillion's head seemed to hang suspended in the air while the darker body merged eerily into the deep shadows. The reddish eyes burned like angry gas jets on their thick probing stalks and the beak hissed and flapped behind the gleaming white sabre fangs. The monstrous head nodded menacingly at each squeaking step as the giant curved talons scratched at the polished rock floor; the jerkily clutching claws flashed in the light as the creature swung ponderously from side to side, sniffing out its prey.

The Doctor waited until the thing was almost upon him. Then he rose to his feet, keeping his back to Koquillion. 'Come in, come in. I have been expecting you for some time,' the Doctor declared, his firm authoritative voice echoing impressively around the vault above.

Koquillion stopped in its tracks with a fractured squawk of surprise.

Very slowly the Doctor turned to face the hissing dragon across the burnished stone altar. Like a beast from the underworld, Koquillion loomed through the tangle of coloured shafts of light which reflected from the polished slabs.

'This used to be the Didonian Hall of Judgement,' the Doctor said with a grandly sweeping gesture around him.

'Their equivalent of a Supreme Court, I suppose.' The Doctor smiled, his face an almost skull-like mask, hollow-eyed and hollow-cheeked under the overhead illumination.

'Rather appropriate in the circ.u.mstances, do you not agree?'

Cautiously the Doctor walked round the altar and stopped in front of the glowering monster. 'Koquillion, perhaps I should remind you that...' The Doctor's voice seized in his throat and he dived sideways just in time to avoid the slashing razor claw as Koquillion lashed viciously at his face.