'They seem very sure, Ian,' whispered Barbara, 'And remember the police box, the difference between the inside and the outside.'

'I know...' Ian looked challengingly at the Doctor. 'Well, are you going to open those doors?'

'No.'

Ian looked at the two girls. 'You see. He's bluffing.'

'Not until I'm sure it's safe to open them,' said the Doctor patronisingly. He checked some more readings. 'The air seems very good. Yes, it is, it's good, quite remarkably unpolluted. Check the radiation counter, will you, Susan?'

'It's reading normal, grandfather.'

'Good, good. I'll take a portable Geiger counter, just in case.

So, young man, you still challenge me do you?'

'Just open the doors and prove your point,' said Ian wearily.

'You really are too narrow-minded, my dear boy,' said the Doctor, with an air of insufferable superiority. 'You must learn not to be so insular!'

'Have you any idea where we are, grandfather?' asked Susan.

She passed the Doctor something that looked like a small black box.

'Oh, we've certainly gone back in Time... a considerable amount, I think. When we get outside, I'll take a few samples... some rock pieces, a few plants... then I'll be able to make a proper estimate.' He looked reproachfully at the TARDIS console. 'I do wish these instruments wouldn't keep letting me down, though.'

'You really believe it all, don't you?' said Ian incredulously.

'You really believe we've gone back in Time.'

'Oh yes,' said the Doctor complacently. 'Without a doubt!'

'And when we open the doors, we won't be in a junk yard in London, England, in 1963?'

'That's quite correct. Your tone suggests ridicule, young man.'

'Well, of course, it's ridiculous! Time doesn't go round and round in a circle. You can't just step off wherever you like, in the past or in the future.'

'Oh? And what does happen to Time then? Instruct me!'

'It... well, it happens,' said Ian vaguely. 'And then it's finished!'

There was condescending amusement in the Doctor's manner.

He looked at Barbara. 'And what about you? You're not as doubtful as your friend, are you?'

'No. No, I don't think I am.'

'Good! There's hope for you yet.'

Ian sighed. 'Oh, Barbara.'

'I can't help it, Ian. They're both so calm, so certain of themselves. I just believe them, that's all!'

The Doctor stared hypnotically at Ian. 'If you could touch the alien sand with your feet, hear the cries of strange birds, watch them wheel above you in another sky... would that satisfy you?'

'Yes,' said Ian simply.

The Doctor smiled, reached out and threw a switch. 'Then see for yourself.'

The TARDIS doors slid open.

Ian went to the open door and stared out. 'It's not true,' he said.

'It can't be!'

The Doctor smiled.

5

The Disappearance

Beyond the door was a bleak and sandy plain, scattered with enormous boulders. It stretched to the edge of a dense, impenetrable forest. To the left, low rocky foothills rose to merge with distant jagged mountains. Away on the right, beyond the forest, you could see the glint of a broad and sluggish stream.

The plain was scoured by winds which made a constant, low moaning sound, and the air was crisp and chill. It was a grim, forbidding scene.

The Doctor sniffed triumphantly and said, 'I've no more time to argue with you, young man. Susan, I'm going to collect some new samples.'

He strode out onto the plain as confidently as if it was the junk yard in Totters Lane, and vanished behind the TARDIS.

'Be careful, grandfather!' called Susan.

'Let's go outside and look,' said Barbara. She stepped outside.

Ian moved towards the door and winced. 'Ouch!'

Susan came back to him. 'What is it, Mr Chesterton?'

'Got a bit bruised in the fall. It's nothing much.'

'Come on, lean on me.'

Ian put his hand on her shoulder, and walked stiffly through the door. It closed behind him.

Coarse sand crunched beneath his feet, and he shivered in the wind. The air was cold, but incredibly clear, and in the distance, the forest, the river and the mountains stood out in sharp-edged detail.

'Well?' asked Barbara mischieviously.

Ian shook his head. 'There must be some rational explanation -

there must be!'

In his heart, Ian knew that only one explanation was possible.

Everything the Doctor had told him was the truth. With those first steps outside the TARDIS, Ian began to accept the reality of the whole extraordinary situation.

The Doctor popped into sight from behind the TARDIS, looking distinctly peeved. 'It's still a police box. Why hasn't it changed? Dear me, how very disturbing!' Shaking his head the Doctor marched off, disappearing behind an enormous boulder, leaving Ian gazing after him in astonishment.

The Doctor walked on for some way, threading a path between the great stones, brooding over the erratic functioning of the TARDIS. Recollecting the purpose of his expedition, he came to a sudden halt, and found he was in a kind of sheltered enclosure between two great rocks. Deciding that this spot would do as well as any other, the Doctor fished out his Geiger counter, a small leather-bound notebook and a pencil.

Picking up a fragment of rock, he began examining it with great care.

Soon he was quite absorbed in his work - and quite unaware of the savage, skin-clad figure watching him from behind the rocks.

The Doctor's companions meanwhile were making a cautious exploration of the area immediately around the TARDIS.

Barbara came across the skull of some large animal half-buried in the sand, and she and Susan began digging it free with their hands.

'What do you think it could be, Ian?'

Ian helped them to clear the sand from around the skull. 'I don't know. No horns or antlers. Could be a horse or a deer - could be anything.' Ian looked back at the TARDIS, standing blue and square and incongruous, but undeniably there in the middle of the sandy plain. 'Incredible. A police box in the middle of nowhere. It just doesn't make sense.'

Susan glanced back at the TARDIS. 'It's supposed to change shape,' she said matter-of-factly. 'I don't know why it hasn't done it this time.'

'It's supposed to what?'

'Change its shape,' repeated Susan. 'It's been an Ionic column, and a sedan chair... it ought to be a boulder or something now.'

'You mean the ship disguises itself wherever it goes?' said Barbara.

'Well, it's supposed to, but it just hasn't happened this time.

The chameleon circuit must be faulty.' Susan stood up. 'I wonder if this skull would be any help to grandfather... Where's he gone?' She turned slowly in a circle, shading her eyes with her hand.

'Grandfather!' she called. 'Where are you, Grandfather?'

There was no reply.

Barbara looked at Ian. 'You're very quiet.'

'Humbled is the word. I was wrong, wasn't I?'

'I don't understand it any more than you do,' said Barbara. 'The inside of the ship, suddenly finding ourselves here... not to mention most of the things Doctor Foreman says.'

'That's not his name. Who is he? Doctor who? Perhaps if we could find out who he is, we'd have a clue to all this.'

'The point is - it's happened, Ian. We've just got to accept it.'

'It's almost impossible to accept. I mean, I can see we're here, but...' Ian shrugged helplessly.

Susan said, 'I can't see him! I can't see grandfather anywhere.'

'He can't be far away,' said Barbara reassuringly.

'I felt strange, just now... as if we were being... watched.' Susan raised her voice. 'Grandfather? Where are you?'