When Za and Hur moved into the clearing, the great beast's dilemma was resolved. It knew the cave people of old, knew the way they looked and moved and smelt, knew how they hunted with spears and axes.

Lashing its tail, the tiger snaked through the forest towards the two newcomers.

In the clump of bushes, Ian whispered, 'Keep down all of you.

Not a sound!'

Za looked round uneasily, sensing rather than seeing something wrong.

He touched Hur's arm. 'Wait here,' he whispered. 'There is danger in this place. I will go and look.'

Za moved cautiously into the clearing, heading straight for the bushes where Ian and his companions were hiding. From somewhere behind him, there came a low growl.

Za swung round. It was the voice of the tiger, the long-toothed one, the old enemy of his people.

Grasping his axe tighter, Za swung his head from one side to the other, listening, sensing.

Just behind him the long grasses began to ripple. Hur saw it and screamed a warning, but it was too late. The tiger sprang.

9

Ambush

As the tiger hurtled through the air towards him, Za seized his only possible chance. He ran, not back but forwards, under the attacking beast, and swung his great stone axe with all his strength at the creature's side.

He felt the axe-head thud home. The tiger screamed in rage and pain. Its whole weight dropped full upon him, bearing him to the ground.

Za tried to wrench back his axe for a killing blow at the skull, but only the handle came free. The axe was broken...

To the Doctor and the others, everything seemed to happen in a blinding flurry of speed. They saw the great beast spring, bearing the caveman to the ground.. They heard the tiger scream...

In a flash of yellow fur, it broke free and disappeared into the forest, leaving the blood-covered form of the caveman stretched out in the moonlit clearing.

The girl gave a great cry of grief, and ran to kneel beside him.

Ian jumped to his feet. 'Quick, now's our chance. Get away all of you. Run!'

Instinctively, the others obeyed him. All except Barbara, who stood looking back at the two figures.

'What are you waiting for?' shouted the Doctor.

'We can't just leave them!'

'My dear Miss Wright, they are savages. They would cheerfully have killed us. Remember the skulls in the cave.'

'I don't care what they've done, they're still human beings.'

Barbara began walking across the clearing to where the sobbing girl knelt by the motionless body of the man. 'I think he's dead. There isn't any danger.'

'Barbara, come back,' shouted Ian running after her. 'This is our chance to escape.'

'I'll come with you, Barbara,' called Susan. She moved to follow, but the Doctor caught her arm. 'You will do no such thing, Susan. Stay where you are. We're going back to the ship!'

'No, grandfather,' said Susan defiantly. 'We can't leave her here alone.'

The Doctor looked across the clearing and said exasperatedly,

'What are they doing? Are they out of their minds?'

Crouched protectively over Za, Hur looked up fiercely as Barbara and Ian approached. 'Keep away!'

'Let me look at him,' said Ian.

'No. You will kill him.'

Gently Barbara pulled Hur aside, as Ian knelt beside Za's body.

'It's all right,' said Ian. 'I'm your friend.'

Hur looked at him in amazement. 'Friend?'

'I shall need some water.'

'Water?'

'Get me some water,' said Ian patiently. 'For his wounds.'

Hur pointed. 'There is a stream - over there.'

'Show me,' said Barbara firmly, as though addressing a reluctant pupil. 'Give me your handkerchief, will you, Ian?'

Muttering and grumbling, the Doctor allowed Susan to lead him over. 'It's all right, grandfather,' said Susan soothingly. It's quite safe now.' The Doctor snorted in disgust.

Susan looked down at the caveman. 'How is he, Ian? Is he dead?'

'Far from it,' said Ian. 'In fact, he's a lot better than he looks.'

He picked up the haft of Za's axe. 'I imagine he must have left his axe-head in the tiger.'

Barbara and Hur came back into the clearing. Barbara gave Ian his water-soaked handkerchief, and Hur carried more water in a folded leaf.

Ian began washing away the blood from Za's wounds, which were soon revealed to be no more than a series of deep slashes in his arm and shoulder. 'Most of this blood is the tiger's,' said Ian.

Barbara pointed. 'Look, there's a cut in his forehead - the tiger must have stunned him.' Ian bathed the cut, and Za moaned and stirred. Ian looked ruefully at Barbara. 'We seemed to have missed our chance of getting away. I bet your flat must be just littered with stray cats and dogs.'

'They're human beings, Ian,' said Barbara again.

'All right, I know.'

Ian looked up at the Doctor, who stood scowling down at them. 'Have you got medical supplies in the ship? Antiseptic?'

'This is preposterous,' spluttered the Doctor. 'One moment we are desperately trying to get away from these savages and now -'

'Now we're helping them! I know. You're a Doctor. Do something.'

'I am not a Doctor of medicine, young man.'

'Grandfather, we should make friends with them,' urged Susan.

'Maybe they'll help us.'

'Ridiculous!'

'Why?' said Barbara angrily. 'Why must you treat everyone and everything as less important than yourself?'

The Doctor looked severely at her. 'I suppose you think that everything you do is reasonable, and everything I do is inhuman. But suppose your judgement's wrong, not mine? If these two savages can follow us, so can their fellows. The whole Tribe may be upon us at any moment!'

'The Tribe sleeps,' said Hur.

'And the old woman who set us free, mm? What about her?'

'You're right, Doctor. We're too exposed here.' The Doctor nodded complacently - but his expression changed rapidly when Ian went on, 'We'll make a stretcher and carry him with us!'

'You're not proposing to take him back to the ship?'

'We can make the stretcher with our coats,' said Ian briskly.

'Barbara, Susan, see if you can break off a couple of long straight branches from those bushes.'

As she moved away, Barbara said, 'Maybe the old woman won't give us away. She helped us, she won't want the others to know.'

'Do you think these people have logic and reason,' said the Doctor furiously. 'Can't you see, their minds change as rapidly as night follows day. She may well be telling the entire Tribe at this very moment...'

Sometime in the night Kal woke, warned by some instinct of danger. He looked around him. Everything seemed normal. Then he saw that Old Mother was gone. And Za and Hur... Something was happening. Whatever it was, it must be concerned with the strangers.

Za had betrayed him, he was trying to force the strangers to give him the secret of the fire.

Kal rose, knife in hand, and made his way stealthily to the cave of skulls. His suspicions were confirmed, when he saw that the great stone had been moved aside.

He slipped through the gap and saw to his astonishment that the cave held no strangers, and no Za. Only Old Mother lay moaning on the ground.

Kal dragged her to her feet. 'The strange creatures - where are they?'

'They have gone,' said Old Mother, a gleam of triumph in her eyes.

'How did they move the stone?'

'Za moved it.'

'Za has gone with them? Tell me, old woman, tell me!'

The old woman pointed to the back of the cave. 'Za and Hur went after the strangers. Through there. There is another way.'

'The strangers' hands and feet were bound,' said Kal fiercely.