CHAPTER 11.

It had been the wink that had finally done it. Sam had been fairly sure that the Doctor was acting, before that, despite the alarming symptoms. But that wink, when she'd leaned over him in the garden. So playful, so let's-fool-the-baddies, as if they were still fighting Zygons. She'd almost said it then, she'd actually started to say it: 'He's just pretending. He's got a reason 'He's just pretending. He's got a reason for going back to the ship that he's not telling you about.' for going back to the ship that he's not telling you about.' But she hadn't quite dared. It would feel too much like betrayal. But she hadn't quite dared. It would feel too much like betrayal.

More importantly, she hadn't known how the Tractites would react. They might kill the Doctor. They might kill her or worse, not kill her, and leave her on her own in an alien universe for the rest of her life.

But, even so, it had to be wrong to let the Doctor destroy this world. There had to be another way, an easy alternative that wouldn't mean anyone getting hurt.

She just couldn't think of one.

Kitig had been carrying the Doctor across his back in a large wicker pannier; for the journey, he'd put it down on the deck of the skimmer. The basket had a padded lining, smelled faintly of citrus fruits, and looked more comfortable than most beds. The Doctor appeared to be, quite simply, asleep. His hair fell around his head, shining in the sun like the halo of a saint in a medieval painting. Kitig and Narunil stood at the tiller of the skimmer, their cheeks touching. They seemed tense but then they thought the Doctor was ill, possibly dying. Maybe they thought they were to blame for it.

And I can't explain, thought Sam. That's the worst thing. If only there was someone to talk with. Someone who would understand.

The skimmer was flying over marshland now, the Tractite city of Afarnis invisible in the glare of sunlight on water behind them. In this light, the marshland was a different world: the dull reeds now glowed in startling greens and yellows; the water was bright blue; even the mud banks that formed the sides of the islands seemed clear, alive with shades of sandy brown and dark shadow. Wading birds stood in the water, waiting for passing fish. A solitary willow tree stood on a small, hunchbacked island, and a pair of falcons were perched on a dead branch, watching the landscape.

This was Earth as it was meant to be, thought Sam. Clean, wild, almost infinite in its variety; and, yes, a few cities spotted here and there, what was wrong with that? The difference was, the Tractites had it under control. No drugs, no wars, no starving millions, no smoggy monoculture destined to get slowly worse and worse for the next thousand or two years and then if the Doctor was to be believed simply cease to exist. Instead harmony, balance, perfection. And it had gone on for millions of years.

How could the world be so beautiful and so difficult to handle at the same time?

Suddenly Sam thought of something. A way of hinting at the truth but something that she could retract if it looked as if the Doctor was in serious danger.

'Kitig,' she said slowly. 'You said that you thought the Tractites might have got to Earth that is, here, to Paratractis by time travel.'

Both Kitig and Narunil looked round sharply.

'I've been thinking about that,' Sam went on, 'and I don't think it makes any sense. Time travel isn't possible. If you could have time travel then well for example, the Doctor and I could just go back in time and stop the Tractites from ever coming here. Then the place might fill up with oh, I don't know. Talking giraffes. Insectoids. Perhaps even bipeds, like us.'

She said the last words slowly, holding Kitig's humanlike day eyes with her own.

Kitig looked down. 'Yes,' he said. 'I see that it's possible.' He was silent for a moment. 'It's also possible that Tractites could do the same to the bipeds. The cycle could go on for ever.'

Sam fancied that she could hear a sharp intake of breath from the Doctor, behind her. Was that what he was afraid of, then? An infinitely repeating loop of mutual genocide?

The skimmer swayed slightly, and Sam realised that Narunil had taken a step towards her. The Tractite stretched out her arms so that they almost touched Sam's body, lowered her huge head as if she were about to charge. Sam could feel her breath, warm, scented of musk and grass.

Suddenly Sam felt afraid. She realised that if Narunil wanted to kill her, she could very easily do it. One kick would be enough.

'Narunil,' said Kitig. 'We're almost there. Could you help me lift the Doctor's basket on to my back?'

For a moment, Narunil didn't move, then she slowly stepped backward, one leg at a time, her eyes still on Sam.

'Narunil,' repeated Kitig.

Sam swallowed. 'I'm sorry,' she said. 'I didn't mean to frighten you. Time travel's impossible, of course.'

'Of course,' said Kitig quietly.

Sam sat down at the edge of the skimmer, watched as Narunil lifted the Doctor in his basket up on to Kitig's back.

Had Narunil been going to hurt her? It seemed an overreaction to what she'd said. Even if the Tractite had guessed that it was a warning, then surely it would have been more sensible to ask her some questions.

But they weren't asking anything. The skimmer was landing, and there was the TARDIS still parked on its mud bank, with a small brown wading bird perched on top. The bird flew away in alarm as the skimmer crunched into the reeds.

Then the skimmer's force field went down, and cold damp air hit Sam's face. There was a wind on the marshes: the reeds were stirring, rattling. The bird was calling out, a steady, piping note. Other birds joined in.

Alarm calls. Warnings.

The humans are coming.

Sam remembered the Tractite book: the starship, the burning light. Perhaps the Tractites didn't need to ask any questions. Perhaps they already knew.

Had Narunil been going to kill her?

Kitig stepped down from the skimmer, balancing the basket with the Doctor in it carefully on his back; Narunil stayed by the tiller. Sam walked past, her steps unsteady.

But Narunil did nothing, said nothing.

Sam followed Kitig, keeping a safe distance from his powerful rear legs.

The TARDIS door opened. Kitig paused outside. 'Just keep walking,' said Sam. 'It'll let you in, if you've got the Doctor.'

Kitig took another step, another, then seemed to vanish through the door, even though it was far too small for him to pass through. There was an intake of breath from Narunil behind her; Sam hastily followed Kitig. She heard the familiar low hum of the console room around her and heard the ticking of the clocks.

The Doctor was sitting up in his basket, smiling. 'Wonderful!' he said. 'I feel much better already! Now if I can find the myalgesic medication ' He sprang over the side of the basket, rushed across to the console.

No medication there, thought Sam. More lies.

Kitig was looking up, his eyes wide with wonder. Sam followed his gaze, saw the vast blue-bronze height of the console room. It somehow seemed to merge with infinity, the heavy substance of the console arms and distant walls gradually becoming pure light. The Doctor had never explained adequately whether it actually had a roof or not. 'It used to,' was all he would say. 'Can't think where it's got to.'

There were clicks and thumps from the console. Sam sat up, saw the Doctor fiddling with controls. He looked up, saw her watching, popped a jelly baby into his mouth.

'Medication,' he explained. 'I feel fine now, but it's best not to take any chances. Would you like one?' He advanced towards her, holding a bright-red jelly baby.

Sam screwed up her face. She didn't like the sickly things at the best of times, and the red ones were her least favourite.

She shook her head.

The Doctor's eyes met hers.

'They're good for you,' he said.

Reluctantly, Sam took the sweet and put it in her mouth.

'An infinitely repeating loop of mutual genocide,' said the Doctor, speaking very quietly.

Sam felt her stomach turn over.

He knows everything of course. He wasn't asleep on the skimmer. He overheard what I said. He overheard what I I thought thought.

Well, that's not really a surprise. But I'm still going to find another way. There must must be some other way, whatever he says. be some other way, whatever he says.

'The effects of the medication can be a bit alarming,' the Doctor said suddenly. 'Kitig, I wonder if you would be so kind as to leave Sam and me for a few minutes.'

'Of course. I hope that you recover soon, Doctor.' He trotted slowly towards the doors. 'Remind me to ask you about this dimensional displacement effect at some time,' he commented over his shoulder, waving an arm around him at the vast dimensions of the console room.

Sam stared after him, bewildered. He seemed almost ludicrously unsuspicious. Did no one on this planet ever pull a fast one?

As the doors closed behind Kitig, the Doctor remarked, 'That was a bit of a chance you took, on the skimmer.'

'I know,' said Sam simply. She looked at the floor. 'I just wanted to find out how much they knew.'

'Yes. And did you?'

Sam shook her head.

To her relief the Doctor didn't say any more, but returned his attention to the screens above the console. They had lit up, become windows to a world of animated mathematics: scrolling lines of equations, three-dimensional helices with bar graphs inside them, moving bubbles whose surfaces were whirling drifts of symbols. The Doctor pulled on a chain that brought one of the displays to eye level, watched it for perhaps half a minute, then nodded.

'We're in trouble, Sam.' He gestured at the display, which had now settled down to show a succession of blobs and bars.

They meant nothing to Sam, but the Doctor had evidently forgotten that, because he went on, 'You can see the problem. The quasi-stable flux interference the blue stuff is the original universe, that's the one we came from. It's stable enough, but shrinking. The rest is just a series of interference patterns.'

Sam looked at the screen, then at the Doctor. 'Which means?' she prompted.

'I don't know...' The Doctor pushed a few more switches on the console. 'I daren't take off. We might never land again.

The whole multiverse could fall into the vortex, Sam, just dissolve as if it had never been there.'

Sam thought through what the Doctor had said, unravelling every word, as if it was some particularly difficult concept in GCSE maths. Finally she said, 'Interference patterns between what and what?'

'I don't know. Kitig's listening at the door. Possibly there are several alternative universes, just as you said at the beginning but that isn't supposed to happen, it can't possibly stabilise, ever. Unless...' He paused, put a finger to his mouth. 'It has to be something to do with us.' He jumped up suddenly, grabbed Sam's arms and swung her round like a child. 'Yes!

That's it! We're We're doing it!' doing it!'

Feeling slightly dizzy, and with her mouth still tasting of sickly jelly baby, Sam tried to collect her thoughts. 'So what are we doing that's making ' she began.

'I don't know know,' said the Doctor. 'There has to be something else going on.'

It's at least the third time he's said that since this thing began, thought Sam. A strange feeling came over her, as if she were watching herself on video, or perhaps watching her own thoughts, ticking like the TARDIS clocks, lots of different ticks all mixed up together.

Perhaps I'm going to faint, she thought.

Then suddenly the console room came back into focus, and she remembered something. 'Did you say Kitig was listening to us?'

The Doctor grinned. 'Don't worry, he can't hear anything.' He looked at the screen again, frowned. 'It's shrinking.' His voice had changed again: solemn, almost afraid.

'What's shrinking?' asked Sam, although she was fairly sure that she knew.

'The original universe. The stable part of the vortex. Let me see, I might be able to get us back to ' He pounced on the console, attacked switches and levers. 'Oh, no no. No, no, no, no, no no!'

Sam looked at him, feeling that strange sense of displacement again. She couldn't destroy Kitig's world, but she had to if she wanted to go home but she couldn't but she had to but she couldn't couldn't it was so it was so right right it was so it was so beautiful beautiful...

'We're losing the eighties,' the Doctor was saying. 'And everything back to 2002 in Earth terms, that is has already gone. What's left is shrinking fast. But wait a minute no, that's not right. That can't can't be!' He was shouting. Sam heard the deep rumble of the TARDIS powering up. be!' He was shouting. Sam heard the deep rumble of the TARDIS powering up.

'Doctor, we've got to let Kitig back on board.'

'What?'

'It's his world too. He has to be here. He has to help us decide.'

The Doctor was just staring at her. She jumped forward and hit the door control with her palm. Kitig was kneeling outside in the bright sunlight, his shoes and legs covered with mud. He sprang back as the doors opened.

'I'm sorry, I thought ' he began.

'Get in!' shrieked Sam. shrieked Sam.

'Sam, what are you doing? You can't possibly save him, you can't save any of them and anyway what would be the use use?

He'd be just as stranded as we are! Sam, please, you've got to ' His hand was trying to push hers off the door control. The TARDIS was screaming, a noise Sam had never heard before, and if only she knew what was happening, if only she knew what to do 'Get in in!' she bawled at Kitig.

And suddenly he jumped, a great show jumper's leap through the strange geometry of the door.

The Doctor knocked Sam's hand away from the control, hard, and the TARDIS jolted, rolled like a ship at sea, roared.

Sheets of light fell around the console, controls sparked, screens flashed warnings.

'Oh, Sam,' said the Doctor, bowed over the console. 'Sam, Sam, Sam, Sam. What have you done?'

Sam stared at him for a moment, glanced at Kitig, who was looking wildly around the console room with his smaller, human-style eyes. And suddenly she knew. She knew what she'd done, she knew what to say.

And she knew she was right.

'I've saved Kitig's life,' she said. 'Did you want me to leave him behind to die?'

For a moment the Doctor said nothing. Sam felt her muscles bunch with unexpected anger. Of course he couldn't say anything. She was right.

Kitig was still staring around him. The TARDIS was still pitching like a ship at sea.

The Doctor said, 'Sam, listen to me very carefully, because the future of the entire multiverse may depend on whether you understand what I'm going to tell you.'

Sam drew a breath, ready to argue, then took a look at the Doctor's face and thought better of it.

'Time itself is losing cohesion. If complete instability occurs everything goes into the vortex: your Earth, Kitig's Earth, every star and galaxy and quasar and black hole and everything that ever was or will be or might be. The entire multiverse will collapse like a sand castle in front of the tide.'