'There is an easy way out of our situation.'

'I-you've found something? Quick man, tell me,' said Viner.

'Of course,' said Klieg icily. 'You're forgetting something. A simple law of logic. If it closes it can be opened. From here.' He pointed to the central control.

'Conveniently labelled in symbolic logic, I see,' said the Doctor.

He examined the lever shape. 'Fits a human hand too. Hmmm!'

'You mean-not a Cyberman hand...' said Jamie, next to him, beginning to get the idea. 'Why would they do that?'

The Doctor did not answer, merely glancing expectantly at Klieg-waiting for his move.

'So,' said Klieg crisply. 'There is a simple way out again. Via this control.' He turned back to the. board followed by the others.

'If you will stand clear, I will operate the sequence.'

'If it is is the opening device,' said the Doctor softly. the opening device,' said the Doctor softly.

'It is obviously an opening device of some kind, Doctor,' said Klieg, smiling.

'Hurry it up. I don't know how you can all be so blasted calm about it,' blurted Viner. 'I'm half frozen.'

Jamie looked at him in disgust. 'If you'd help for a wee change,' he said, 'instead of always moaning.' He started back along the tunnel.

'I'll tell you if it works,' he called to the Doctor and Klieg. 'Go ahead.'

Decisively Klieg followed a simple sequence of levers and coloured b.u.t.tons. The switchboard lighted up and the dynamo-like hum told him the controls were working. Klieg finished his sequence, watched closely by the Doctor, then stood back with arms folded, watching the dials.

There followed what seemed like an endless pause to the waiting men.

Then Jamie entered, out of breath and despondent. 'Nae, it didna work.'

Viner turned away stricken. They all looked along the icy tunnel, as though it could somehow show them the opened hatch and that everything would be all right. Even after they had realised that the hatch would not open, the others stood silent, each with his private thoughts.

The Professor felt something on his cheek. Something that in normal circ.u.mstances he would hardly have noticed-a drop of water. He brushed it away, then his mind registered the significance of it.

'Water!' he said aloud. Drops of water were beginning to fall all over the cavern now.

'It's getting warmer,' said Jamie.

With the warmer air the light inside the cavern was steadily increasing in intensity. The three-storey honeycomb of cells seemed to be illuminated from behind. The huge curled-up Cybermen were becoming visible in sharp focus as the ice melted from the outside of.

the clear plastic membranes.

There was something threatening in the three banked rows of insect-like figures as the cavern lightened. Only the Professor seemed impervious to the threat-like a happy child he reloaded his camera and darted forward, recording his find for posterity.

'Perfect! Perfect! Gentlemen!' he called to the others. 'They are in perfect condition. This is unique in archaeology.'

It was Viner who noticed it first.

'Professor,' he called, pointing to the nearest Cyberman. 'I'm sure that one moved!'

'Nonsense,' said Parry.

'No, he's right.' Jamie's keen eyes roved over the now defrosted cells. 'Look! Up there.'

In the middle of the second row of cells, one of the Cybermen was visibly stretching his body-stiffly, one small jerk at a time, like a chick emerging from an egg.

'My G.o.d!' Viner's voice had shrunk to a whisper. 'They're all all moving!' moving!'

The process of defreezing had now accelerated. Water was streaming clown the side of the honeycomb and 'running away in specially built gullies. The air in the cavern was now oppressively warm and humid.

All over the honeycomb the Cybermen were coming to life, their huge limbs illuminated from behind in a slow-motion shadow ballet.

The men stared, as if hypnotised. Viner finally broke the silence.

'You fool!' He turned to Klieg. 'You must have worked the wrong controls. We must shut it down-quickly!'

He rushed to the control panel and with an insight bred of desperation, managed to reverse the 'start-up' sequence activated by Klieg.

Almost immediately cold air began to blow into the cavern, once more the sheets of water froze against the honeycomb. Inside the cells the Cybermen's movement stopped and they froze back into immobility like run-down clockwork dolls. The light began to fade once more.

Klieg, who had been watching, as hypnotised by the terrible ballet as the others, snapped back into life.

'What... what is happening?' He swung back on Viner, his eyes wild. 'Get away from those controls.'

Viner raised his slight body to its full height and stared back at Klieg through his gla.s.ses. 'Certainly not!'

Klieg put his hand into the inside pocket of his coat and brought out a small but deadly handgun.

'What are you doing, man?' The Professor was now hopelessly bewildered by events. Jamie stepped forward but was blocked by the giant Toberman, arms folded, protecting Klieg.

'Keep back.' Klieg's voice rose in pitch and emphasis. 'All of you. I shall not hesitate to kill. For the last time.' He turned to Viner.

'Stand away from those controls.'

The little man, whose nagging anxieties and complaints had got on the nerves of his companions throughout the expedition, now showed an unexpected reserve of will and courage. He stared unflinchingly into the mouth of the levelled gun.

'Put that away. You can't intimidate me.'

There was a sharp stinging crack, a wisp of smoke, and then Viner reeled back against the control desk, his hand clutching his chest, an incredulous look on his face. He tried to speak, his eyes widening behind his gla.s.ses, and then sagged slowly to the ground.

'You've killed him!' Parry stared from Klieg to Viner, almost unable to realise what had happened to his well-ordered world.

'He's mad!' Jamie's dirk gleamed in the light from the control panel and he started forward, only to find the Doctor's arms around him, pinioning him with unexpected strength.

'Wait, Jamie,' he said.

He was just in time. Klieg had raised the gun again to fire at Jamie. Now he replaced it in his pocket and sprung' back to the controls-his finger stabbing a staccato tattoo on the b.u.t.tons.

Again the lights came up behind the cells, the air changed to a warm blast and the ice melted-a much quicker process this time.

'Haydon dead, and now poor Viner,' said the Professor. He looked at Klieg in horror. 'What kind of man are you?'

Klieg drew out his gun again and placed it close to hand on the control console. 'You will soon find out,' he said. 'Now, back, all of you. Over there.' He pointed to a spot against the rock wall opposite the Cybermen tombs.

'Let us see what happens now,' he continued. 'As you said- this a unique archaeological event. It would be such a pity to miss it.

Now stay quiet-and watch.'

He motioned to Toberman, who stooped down, picked up Viner's body as easily as a rag doll and placed it over by the others.

The Professor bent over his colleague and looked up at the Doctor, who shook his head sadly.

'Look, Doctor-have ye ever seen anything like it?'

The honeycomb had cleared of ice once more and, as they watched, the Cybermen were slowly uncurling and stretching. At last the most advanced one, now in a sitting position, raised his steel fist and struck sideways, as at a gong, at the plastic membrane.

The plastic split under the blow.

Another blow from his fist and the membrane was in shreds like a split drum. The Cyberman stiffly rose up and with his arms held out like a swimmer before him, pushed his way out of the cell and stood upright in front of the honeycomb.

The terrible blank stare of the Cyberman swept over the group of humans, to Klieg at the control desk and then back to the honeycomb as he turned to face the other emerging Cybermen. One by one the huge silver giants broke out of their centuries-old cells and climbed down to stand beside their companion.

In the control room above, Kaftan sat by the console making notes on the sequence for opening the hatch. Victoria was still asleep but was making the slight movements that showed the drug was wearing off and she was near waking.

Kaftan glanced at her and then went back to her notes. At last Victoria stirred and opened her eyes. She looked around her.

'h.e.l.lo,' she asked, still somewhere in her sleep world. Then, more alert, she remembered where they were. She turned and saw the hatch was down. 'What's happened? The hatch is down. Oh, good, they're back.'

She shook her head to get the sleep out of it and winced slightly from headache. Then she looked around. There was n.o.body there but Kaftan.

'They are still down there,' said Kaftan, entering another neat row of figures in her little book.

'Then why is the hatch closed?' asked Victoria, her head aching but now thoroughly awake. 'They won't be able to get up again.'

She rose. She looked down at Kaftan.

'I shall open it when we are ready,' said Kaftan quietly, going on with her notes.

'When who is ready?' asked the girl. 'Did you close it?'

'I did.'

Victoria looked at the Arab woman whom she had so admired, confused. There could be no good reason for Kaftan to have closed the hatch. Quickly she adjusted herself to this new character. And knew why she had slept so soundly.

'Then you had better open it again,' she said steadily.

'No,' said Kaftan, still writing. 'It must remain closed.'

And in another flash, Victoria understood why the Doctor had wanted her to stay on the surface.

'The Doctor warned me to keep an eye on you,' she snapped, furious enough to stand up to this sophisticated woman from a future age.

'That was very clever of him,' smiled Kaftan. 'You should have taken more notice of his words.'

Victoria strode up to Kaftan and pushed her away from the controls.

'Out of my way,' she stormed.

'Why?' asked Kaftan with that all-knowing smile that now made Victoria furious instead of submissive.

'Because I'm going to open the hatch,' said Victoria, and reached out for the controls. She looked at the complex rows of b.u.t.tons and levers, bewildered. Still smiling, Kaftan pulled out a small neat gun, similar to the one used by Klieg, and pressed it against the girl's back.

'Now, stand back,' she said gently. 'Games time is over for today.'

Victoria turned round slowly to face her and saw the gun.

There was certainly no doubt now.

'That is better,' said. Kaftan pleasantly. 'Now, let us move away from these controls. We shall be more comfortable over here.'

They moved together away from the controls, back to where Victoria had been sleeping. Victoria sat down, thinking out clearly what to do next. Next to her was her handbag, a comforting bit of her past life, with the hard lump of that funny Cybermat thing in it, that she had put there despite the Doctor... She could have kicked herself for disregarding his advice. But it was too late for that now. If she didn't keep a clear mind they would all be killed. It depended on her alone.

'Why have you done this?' asked Victoria. 'You've trapped your friends down there as well as mine.'

'I shall open it-when Klieg has completed our plans,"