These were the thoughts the deep senses were responding to. Not her conscious commands. The rest of her body, the rest of the ship, was trying to unravel the secrets of the Unthinkable City, the codes of logic that governed the movements of Qixotl's other guests. She felt like a tiny head on a bloated body. A ma.s.s of data with a humanoid face.

This was paranoia, then. This was panic. Marie unfolded, the interior structures of the TARDIS wanting demanding to be set free. She felt her arms unravel, revealing weapons systems the size of small moons. Targeting mechanisms, operating on the universe's most complex dimensional levels, began searching the area for suitable victims.

There was something outside. Outside the ziggurat, beyond the material layers of this planet. Waiting for all the delegates to a.s.semble, waiting for the pieces to fall into place. It was a trap, it was all a trap, and very soon the trap would be sprung. Was Qixotl part of it? Was the other Time Lord?

Random particles of matter were thrown up out of Marie's power core, manifesting themselves as droplets of hard sweat on her skin. A million artificial eyes sprang loose in her spinal column, stared out of her body, and went blind. The targeting mechanisms strained inside her arms, then tore through her flesh, desperately probing the world outside. Determined to pin down the threat. Finding nothing.

There was the echo of an explosion. Then came the explosion itself. Then absolute silence.

Mr Qixotl didn't even flinch. He'd felt the aftershock before the blast. As if the detonation had been so important, it had announced its coming long before it had actually arrived.

It was Homunculette who broke the silence. His eyes were bulging out of his skull, now. 'We're under attack,' he hissed.

Mr Qixotl swallowed. 'It was nothing, Mr H. Really, it was nothing. Maybe one of the matter augmentors backfiring, yeah?'

'Would that represent any real threat to our safety?' asked Cousin Justine. Her voice was calm and quiet, so everybody ignored her.

'You think I don't know what an attack sounds like?' Homunculette shrieked. 'That was some kind of plasma burst, or... I don't know...'

'Dimensional incursion,' said the individual Qixotl knew full well had to be the Doctor.

Homunculette spun around to face him. 'What?'

'You heard the echo. A minor rupture in local s.p.a.ce-time, I'd say.' The Doctor shrugged. 'Not that I'm claiming to be an expert.'

Homunculette was practically boggling his face off. 'Dimensional incursion? What kind of ludicrous techn.o.babble is that supposed to '

Unexpectedly, he fell silent.

'Marie,' he gargled. And suddenly, he was at the doorway, having bounded across the room with a single step.

Qixotl gave a sheepish grin, and made sure everybody in the room got to see it. 'Technical hitch,' he told the reps. Then he followed Homunculette out into the pa.s.sageway.

Homunculette found Marie's body in the main corridor, at the junction between the guest room pa.s.sage and the ziggurat entrance. He didn't recognise it as a body, to begin with. The first thing he saw was the hatstand, propped up against the wall between the torches. After that, he saw the tiles, patches of off-white flooring torn out of the TARDIS interior and scattered along the corridor. A sofa clogged up the side-pa.s.sage to Homuculette's right; he identified it as the shabby red one from Marie's secondary console room, but only half of it seemed to be there, the other being embedded in the corridor wall. An upturned bookcase lay beyond the sofa, vomiting out shredded pages covered in scrawls of High Gallifreyan.

Marie was she was lying there. Not an object Marie the dead heart of Marie lay at the centre of the junction, her spine pressed against the floor, her head tilted at an angle that made her look as though she'd broken her neck. The entire left side of her body was missing. It was as if someone had drawn a line, a smooth contour, from her cheek to her ankle, and torn away everything on one side of it. Her left arm was gone. So was a lot of her face.

She was a person his companion she was his dead Marie's right eye was intact. The left eye was in place, but the skin had been torn away, leaving a pearl of pure black that didn't even bother pretending it was organic. A thing, instead of an organ. An object.

She was she was not an object. She was a person. She was she was his companion. His dead he was bending over her, knees pressing against the broken tiles, the fabric of his suit soaking up cold liquid from the floor. Water. Pooling around her body. Sucked out of the purification system that had been part of dead companion and there were footsteps, wet footsteps. Mr Qixotl, the humans, the man in the ridiculous velvet jacket, and He looked into her eyes, tried to look into her eyes, found himself staring into her head instead. Nothing but static inside her and Mr Qixotl was leaning over his shoulder, gawping at the wound in Marie's side, standing in her lifeblood, her water supply, without even an apology. The man in the velvet jacket was hovering behind him. Spectators. Vultures. Homunculette reached out for Marie, wanting to press his hand against her cheek, but his arm slipped into the wound and vanished into her interior. Homunculette looked up, and met Qixotl's stupid frog-eyed stare.

'You promised security,' he said. His voice was a long, strangulated gurgle. Qixotl looked scared, started to back away. Homunculette stood, felt the urge to stand up and hit the man, to crack his head against the wall and keep cracking until the wound was as big as Marie's.

'She's a TARDIS,' said the curly-haired man. He was staring into Marie's body, transfixed. Surprised.

Alien vulture. It felt almost like a violation, like the man was unravelling every mystery of Homunculette's companion.

Curly-hair jumped back, as a filing cabinet squeezed itself out of Marie's wound and shunted itself across the corridor. The matter left inside her was forcing its way out, piece by piece. Pus from the wound.

'She was attacked,' Homunculette said. He knew there was some kind of feeling in his voice, but he didn't know what it was supposed to be.

Curly-hair looked up at him. 'Maybe not. I'm sorry, I know you're upset. But this doesn't look like an attack from the outside. I don't know of any weapon that could cause an incursion like this. It looks like the damage was done by something internal.' He looked down at Marie again. 'Did... Marie... have weapons systems? Defences?'

'She was my companion,' Homunculette whined. 'Of course she had weapons systems.'

The man nodded. 'I think something triggered them. Altered them in some way. Her own weapons took her apart from the inside.'

'Erm, right.' Mr Qixotl's voice. Even his words sounded like they were trying to sneak away. 'Maybe we should think this through a bit more, y'know, carefully...'

Homunculette closed his eyes. 'Get her back to our room,' he said. He felt fluid trickling down his fingers, and knew it was blood. He'd been clenching his fists, sc.r.a.ping open his skin with his nails. When he opened his eyes again, the curly-haired man was still examining Marie, a gormless expression on his stupid alien face.

'A TARDIS,' he muttered. 'Well well well.'

Another poxy corridor, thought Sam. Great.

After the explosion, things had quietened down a bit. According to the Doctor, they'd stumbled across some kind of alien auction, arranged by the impossibly shifty Mr Qixotl, although n.o.body had bothered telling Sam what was up for grabs here. Qixotl was supposed to be a scheming interplanetary mastermind, but to Sam he'd looked and sounded more like a reject from Only Fools and Horses Only Fools and Horses. Things weren't going well for him, obviously, as the Doctor had gatecrashed the party and one of the other clients had spontaneously self-destructed in the middle of the ziggurat.

'But that's not the worst thing,' the Doctor had told Sam, after Qixotl had helped the woman's companion carry off her body. Her body had consisted not just of an actual corpse, but several pieces of furniture, as well. 'She wasn't human. She wasn't even organic. She was a TARDIS.'

'A... hold on. You're winding me up.'

'I told you before. A fully-functioning TARDIS can look like anything. A motorbike, an Ionic column '

' a sedan chair. Yeah, you've given me the lecture. When you said "anything", I didn't know you meant anything anything anything. I didn't know you meant anything. I didn't know you meant people people anything.' anything.'

'That's because our TARDIS isn't advanced enough to have a fully-developed personality matrix. Marie that was her name, by the way must have been much more complex.'

Sam hadn't commented on the way the Doctor had said "our" TARDIS instead of "my" TARDIS. Touching, that. 'You mean, she was a newer model?'

'Very new. So new, in fact, she doesn't even exist yet.'

Sam had blinked. 'Sorry, is this a weirdzo time travel thing I'm missing the point of?'

'The future, Sam. We Time Lords can't investigate the future of our race. We're like the oracles of ancient Greece, really. We can prophesy everything except our own destinies. Mr Homunculette is a Time Lord, one from an era in Gallifrey's future. How far in the future, I'm not sure.'

'Is that bad?'

'Bad?' The Doctor had looked as though she'd suggested eating live anacondas. 'It could be disastrous. If I learn anything about future Gallifreyan history, causality could he damaged beyond all conception. Even by being here, I'm breaking one of the major haws of Time. I forget which Law it is, exactly. It could be the Third.'

'Terrif,' Sam had said.

After that, the Doctor had stormed off, in the direction of the guest rooms. He'd said he wanted to talk with Mr Qixoti, though he hadn't said why. Sam had been left to wander the corridors alone. According to the Doctor, the place was quite safe, and Qixotl had made sure there were all the comforts an organic life-form could ask for. Sam hadn't bothered pointing out that the place was nonetheless an enormous torchlit pyramid in which one guest had already bitten the dust. Comfort wasn't really an issue.

She stopped at an L-shaped turning. She'd been following a single twisted pa.s.sageway around the ziggurat, and she guessed she'd very nearly come full circle. She only stopped because she saw movement up ahead. A spot of light. Like the torchlight, only smaller, not as bright.

Sam crept towards the glow, sticking to the shadows whenever she could. Whatever the Doctor had said about diplomacy, she really didn't want to run into either of the bat-skulls again. She got the feeling they were the kind of people who'd been first in line to cut up the frogs in biology cla.s.s.

As she got closer, she realised the glow was the end of a lit cigarette.

There was an alcove to the left of the pa.s.sage, a stairway up to the next level. Sitting on the bottom step, cigarette in hand, was the skinny dark-haired woman Sam had seen in the c.o.c.ktail lounge. Then, she'd looked nervous; now, she looked shattered, the sweat stains practically welding her shirt to her skin.

The woman looked up. She would have been attractive, if her face hadn't been covered in blue sleep lines and her hair hadn't been drooping over her eyes in sticky black tentacles. Sam raised her hands.

'It's OK,' she said. 'Two arms, two legs, one head. I'm safe. Honest.'

The woman laughed. The laugh turned into a cough. She dropped the cigarette, and stubbed it out with her boot.

'Don't know if they've got any ashtrays around here,' she said. 'You're human, aren't you? I mean, really human.'

Sam nodded. 'OK if I join you?'

The woman shifted to one side. Sam plonked herself down on the step next to her. 'Thanks. Been having a look around this place. Feet are starting to kill me.'

'Uh,' said the woman.

Sam held out her hand. She wasn't exactly sure why she was trying to strike up a conversation like this. Maybe it was a typical human reaction, when there were so many aliens wandering around the place. All those of like genes ended up sticking together, in the end. G.o.d, there was nothing like intergalactic travel to bring out the bigot in you, was there? 'Samantha. Sam. Sam Jones.'

The woman mulled over the hand for a moment or two, then shook it. 'Bregman. Lieutenant Bregman. UNISYC. Uh. In the interests of good civilian relations, maybe you should call me Kathleen or something.' Sam had no idea what UNISYC was, but she nodded anyway. 'You're with the "independent"?'

'What? Oh. You mean, the Doctor.'

'Yeah. Him. He's not one of us, is he?'

Sam tried to get a fix on Kathleen's accent. It sounded vaguely English, but a particularly distorted and Americanised kind of English. With a hint of French, maybe. 'One of who?'

'Us. You know.' Kathleen half-shrugged. 'What I mean is, you're not working for any of the powerblocs on this this planet. You're not here on behalf of Earth. Am I close?' planet. You're not here on behalf of Earth. Am I close?'

Good question, thought Sam. 'I think we're supposed to be non-political. I keep trying to get the Doctor to go Marxist on me, but he won't do it. How do you know he's not human, anyway?'

'Christ knows. Instinct, maybe. All you have to do is get close to them, and you can tell. No one ever tells you stuff like that, do they?'

"Them" meaning "aliens", Sam presumed. 'D'you meet a lot of them in your, er, line of work?' she asked.

Kathleen reached into her backpack, which she'd taken off and rested on the floor between her legs. 'Me personally? Nope. This is my first time in active BEM service. They've never let me near the Bugs before. I think I'm starting to figure out why. This must be that "culture shock" thing I keep hearing about.'

'Everyone gets that,' Sam told her, nodding sympathetically. But she was thinking about her first meeting with the Doctor, her first trip in the TARDIS. She hadn't had any problems then. Like the bits of the brain that dealt with culture shock had been switched off as soon as she'd stepped into the console room. A side-effect of the TARDIS, or something in her genes?

Bregman pulled out a packet of cigarettes, and flicked it open. 'I only joined up so I could get to see the Cybermen. Straight out of technical college. Me, I mean, not the Cybermen. I wouldn't have joined the regular army if you'd held a gun to my head. Soldiers are boring. Cybermen are worth shooting at.' She gave Sam a meaningful glance. 'I was the kind of kid who had VirchCon fighters instead of Barbie dolls. You probably guessed that.'

Sam kept nodding. She'd had Star Wars Star Wars figures, herself. Kathleen offered her the cigarette box. 'Thanks, no.' figures, herself. Kathleen offered her the cigarette box. 'Thanks, no.'

Kathleen grunted, then lit up a cigarette for herself with a disposable lighter, leaving the rest of the packet on the step beside her. 'I wasn't expecting them to be like this,' she said, between breaths of smoke. 'Qixotl. You friend. That Time Lord, what's his name? Homunculette. What I'm saying is, they look human, but they're not. You can tell. Don't know how.'

'Biodata,' suggested Sam. 'Something in the biology. The signals they give off.'

Kathleen shrugged. 'Right now, I'm supposed to be socialising. I think I'll lose my grip if I have to get near Homunculette again. You looked a h.e.l.l of a lot more comfortable around your alien than I I would've done, that's all I'm saying.' would've done, that's all I'm saying.'

'It's not like you expect,' Sam said. 'I mean, being with the Doctor.'

'Yeah? Why, what's it like?'

Sam had to think about that. 'It's like... look, I don't normally talk about this stuff, but I'll tell you, OK? It's like the one time I got totally off my face.'

'The one one time? Are you sure you're human?' time? Are you sure you're human?'

Very funny, thought Sam. Yeah, the one time. The time she'd wanted to find out exactly how liberal-minded her parents were, when it came down to it. 'It was like everything looked out of sync, all of a sudden,' she told Kathleen. 'Like the world had moved two inches to the left, and no one had told me about it. You get paranoid, you get confused...'

'And that's what it feels like hanging around with an alien?'

'No. Listen. After a while, I figured out the best way of dealing with stuff, when you're in that kind of state. You have to act casual. You have to pretend the world's always been that way, and nothing unusual's happening. And that was what it was like, the first couple of weeks I spent away from Earth. It was one stupid situation after another. All these planets I got taken to, all these places where the sky's green or the sea's made out of acid.'

'Let me read between the lines here,' said Kathleen. 'What you're saying is, you went crazy.'

'No. You don't go crazy. Well, maybe you'd go crazy if you tried to fight it, but you don't. You give in to it. Like there's a new set of rules, and you have to go along with them. Does that make sense?'

Kathleen nodded, but Sam got the feeling she wasn't really following a word of it. Because Kathleen hadn't given in to it yet, had she? She was still trying to live in a safe, ordinary, straight-line kind of world, and it was going to drive her mad, if she wasn't careful.

Sam glanced down at the cigarette box, lying on the step between her and the Lieutenant. Sign of normality, she thought. The kind of thing you'd see stuffed down the back of the bike rack at Coal Hill, or lying in the gutters on Kingsland Road. Maybe the packet had been put there as a kind of reminder. A token of the things she'd given up when she'd walked into the TARDIS. A little something from the twentieth century.

She picked up the box, and read the logo on the front.

CLOUD TEN, it read. THE ORIGINAL CANNABIS CIGARETTE. MANUFACTURED IN BIRMINGHAM, ENGLAND.

'You sure you don't want one?' Kathleen asked.

She wasn't dead. His companion there was a hole in her side, but there was a pulse in her heart, the throbbing of engines in the lower levels of her body. Marie was in the guest room, and Homunculette was inside Marie, swimming in the s.p.a.ce between her outer self and her inner self, forcing his way into the console room on the other side of the dimensional rupture.

A heartbeat to guide him. The scent of ions in her atmosphere. She was damaged, she wasn't dead, something in her had shut off the weapons systems in time. A safety protocol. Homunculette felt synthetic air on his face as he dragged himself into the console room. There was hardly any light, only the tiniest of vibrations beneath his feet. Marie's roundels were glowing, but dimly. Dying. Not dead.

She'd been attacked. There was an a.s.sa.s.sin, or a potential a.s.sa.s.sin, right here in the ziggurat. Somebody had violated his companion, probably with a virus of some kind. Somebody had tricked her into activating her defences, letting her weapons systems tear her apart from the inside.

An a.s.sa.s.sin. And it wasn't difficult to work out who.