The Doctor saw Qixotl's teeth clench. 'You've met these things before, right?'

'Twice. This is the first time I've seen one in its low-gravity form, though.'

'And, uh... do they like cheesy nibbles, at all?'

The topmost protrusion of the Kroton's body, the geometric crystal that could, loosely, be called its head, swung around to face them. At least, that's what the Doctor a.s.sumed it was doing, although the creature didn't actually have a face, as such. 'The-av-i-an-life-forms-are-dis-turbed.'

Qixotl looked at the Doctor. The Doctor shrugged. 'Er, that's right,' Qixotl mumbled. 'The toucans, yeah? It's your ship. They're reacting to it a bit badly. You know how avian life-forms are. Listen, there's a guest room all laid out for you downstairs, if you want to freshen up. Or whatever it is you do. I mean, if you don't mind the furniture.'

'The-auc-tion-will-proceed-as-soon-as-poss-i-ble,' the Kroton insisted. 'There-will-be-no-de-lays.'

'No, no, of course not. I'm sure you've got a lot of important things to do back in, er, Kroton-s.p.a.ce.'

'My-des-ig-na-tion-is-E-Ko-balt-Prime-of-the-Kro-ton-Ab-sol-ute. Command-un-it-of-the-Kro-ton-Fifth-Latt-ice.'

'Well ' Qixotl began. But the Kroton hadn't finished warbling yet.

'This-vess-el-was-int-er-cept-ed. The-in-vi-ta-tion-was-dis-cov-ered-in-the-poss-ess-ion-of-its-crew. Your-auc-tion-is-of-int-er-est-to-the-Kro-ton-Ab-sol-ute. My-sup-er-i-or-un-its-in-the-Kro-ton-First-Lattice-have-al-read-y-been-no-ti-fied. A-War-spear-has-been-dis-patched-to-this-plan-et. The-War-spear-will-es-cort-the-Rel-ic-back-to-the-First-Latt-ice-once-it-has-been-sec-ured-for-the-Ab-so-lute.'

That sounded like a threat to the Doctor. Qixotl certainly looked a little taken aback. 'That is, y'know, if you make the highest bid,' the man pointed out.

'Yes,' bubbled E-Kobalt-Prime.

'Can I ask a question?' said the Doctor. 'Where's your dynatrope? I know your people never leave home without one.'

E-Kobalt paused before answering. 'I-will-not-re-quire-my-own-vess-el-to-complete-this-miss-ion.'

'Really? How's your power supply?'

'The-Rel-ic-will-be-sec-ured-be-fore-re-en-er-gi-sa-tion-be-comes-ne-cess-ar-y.' There was a bit more head-spinning. The Kroton's legs quivered underneath its torso. 'The-grav-it-y-on-this-plan-et-is-un-suit-a-ble-for-this-bo-dy. I-will-need-to-re-con-struct-my-ex-ter-i-or-form-im-me-di-ate-ly.'

Qixotl cleared his throat. 'Well, yeah, it's like I said. If you want me to show you to your quarters...'

Before he could finish the sentence, the Kroton shattered. Literally, shattered. The legs disintegrated, allowing the torso to drop to the ground. The body exploded into several thousand shards of translucent crystal on impact, and squashed a few more of the floating plants in the process. There was an almighty cracking sound. Qixotl actually shrieked, but the Doctor merely winced.

All that was left of E-Kobalt was his head (its head, the Doctor corrected himself; Krotons were strictly speaking as.e.xual, although they acted in such a loutish fashion it was hard to think of them as anything but male), plus a shapeless lump of white crystal that had once formed the inner core of the torso. It reminded the Doctor of raw clay in a sculptor's studio, ready to be moulded into something more artistic. head, the Doctor corrected himself; Krotons were strictly speaking as.e.xual, although they acted in such a loutish fashion it was hard to think of them as anything but male), plus a shapeless lump of white crystal that had once formed the inner core of the torso. It reminded the Doctor of raw clay in a sculptor's studio, ready to be moulded into something more artistic.

'Oh no,' squealed Qixotl. 'Don't tell me I've lost another one.'

The Doctor peered at the crystal. 'Don't worry. It's just growing itself a new body. Look.' Even as he spoke, delicate cracks were appearing across the surface of the substance. New limbs were forming under the skin, squirming impatiently as they grew. 'Fascinating. I've never seen this process before. I always a.s.sumed it'd be a private moment for them.'

'Can it hear us?'

'Oh, I shouldn't think so. See, the feelers have dropped off. It hasn't developed new sensory systems yet.'

Qixotl looked distinctly uncomfortable all the same. 'OK, Doctor, let's get serious here. You heard what the life-form said. There's a whole Warspear full of these things coming. Whatever a Warspear is.'

'Yes. And they're not going to be too happy if E-Kobalt doesn't get what he wants at the auction.' The Doctor said it in his best I-told-you-so voice, but Qixotl just shrugged.

'Can't say it bothers me much. Once the property's sold, I'm gone. The Krotons can blow up the whole sodding planet if they feel like it. What I'm saying is, things are hotting up around here. You can't hang about any longer. I mean, what happens if the bidders figure out who you are? We're going to have a riot on our hands, y'know?'

'You should have thought of that before!'

'I was kind of expecting you to stay dead,' Qixotl protested. 'OK, OK. Here's the deal. You go away now, and don't get in the way of the auction, yeah? In return, I'll let you have 40 per cent. Can't say fairer than that, right?'

The Doctor was puzzled. '40 per cent of what?'

'The proceeds. 40 per cent of whatever I get for the stiff.'

The Doctor felt his jaw drop. That hadn't happened in centuries.

'I'll give you your cut the next time I see you around,' Qixotl told him. 'Really. Cross my heart. Universe this small, we've got to b.u.mp into each other sooner or later.'

'You're offering me 40 per cent of my own body?' boggled the Doctor.

'Uh-huh. I mean, don't get me wrong. I'd give you 50 per cent, but I've got expenses to cover here.'

'Don't be ridiculous!'

Qixotl sighed extravagantly. 'If you want to play it like that, fine. But look, if you want your body back, there's no way I can just hand it over to you. Not with this lot around. There's only one way you're going to get your hands on it without causing trouble.'

'Which is?'

'You're going to have to bid at the auction. Like everyone else.'

'Over my dead ' the Doctor began.

He was interrupted by a snapping, crackling noise from the body of E-Kobalt. The new limbs had finished growing. The crystal had split open at various strategic points across the torso, making way for four thick, tube-like extensions. Not crystalline, the Doctor noted; the limbs looked more like some form of flexible metal. One ended in a pincer, one ended in an open tube not unlike a flame-thrower, and the other two ended in flat plates that might have been feet. Presumably, thought the Doctor, the Kroton had some kind of malleable metallic core. Impressive, but hardly efficient. No wonder the things had to suck out peoples' neural energies to stay alive.

A low groaning sound issued from E-Kobalt's head, the one part of its body that hadn't changed shape during the metamorphosis. Flakes of crystal fell away from the Kroton's skin, the torso sculpting itself into something smooth and sharp-edged before the Doctor's eyes.

'Wakey wakey,' he muttered, as new sensory systems began to form across E-Kobalt's body.

Sam threw herself at the wall again. The pink stuff stretched under her weight, but it didn't break. The wall was like a membrane, tough enough to hold her back, but thin enough to let her see shapes moving around on the other side. There, at the centre of the vault, Sam could make out the silver glow of the casket, and the tangle of shadows surrounding it. Kathleen was there, somewhere, lost among the silhouettes of the things that had reached up out of the floor.

The wall hadn't been there a minute ago. It had grown from the brickwork, like something organic. Sam could see purple veins running through the membrane, pulsing in time to the shrieking of the walls. The exit tunnel was behind her, but something red and sticky had stretched itself across the corridor in front of the stairway, a web of razor-fine fibres that looked to Sam like one of those retinal patterns you saw in biology textbooks.

The floor trembled under her feet. She stood aside, and watched as two thick-stemmed flowers grew from the cracks between the stone slabs. The blooms turned to look at Sam, tiny black eyes squinting out of their half-formed faces. Sam tried to ignore the fact that they looked just like Kathleen.

The slabs shifted again, as new shoots forced themselves up into the light. Sam kept side-stepping them, until she ran out of floor and found herself pressed up against one of the vault's solid brick walls.

There was no choice, then. She'd have to make a break for it down the corridor, and deal with the retina-web when she came to it. She'd worry about Kathleen later.

Another shoot exploded from the wall by her ear, spraying her with chips of stone. Sam ducked. The shoot swung to and fro above her head, moving from side to side like an elephant's trunk. Sam didn't move, didn't even breathe. If it was searching for something, it was probably searching for her. She didn't want to give it any clues. Finally, the bud at the end of the shoot burst open.

And there was a baby inside it.

A humanoid baby, the size and shape of an average one-year-old, sculpted out of sticky red bioma.s.s. Its skin was a map of clotted veins, and its big black eyes stared out of a fat, fleshy face. Sam almost gagged. The baby floated above her like a helium balloon, a thick umbilical cord connecting its belly to the bud that had sp.a.w.ned it. It rubbed its eyes, with tiny-fingered hands. Then it looked down at Sam.

It was, without question, the most repulsive thing Sam had ever seen. Not least because it was so familiar. Yeah, its skin was the colour of dried blood and it looked like it had been made out of mincemeat. Yeah, all babies were pretty similar anyway. But Sam's mother had shown her the old photos often enough.

G.o.d, she thought. I never knew I was such an ugly kid.

The whole vault shuddered. The brick wall cracked open from floor to ceiling. Sam threw herself towards the corridor, through a small garden of Bregman-faced flowers. Pink tendrils reached out for her through the hole in the wall, their buds popping open and releasing more of the meat-babies into the air. Sam glanced over her shoulder as she reached the mouth of the tunnel. The babies were at various stages of development, some toddlers, some little more than embryos, but all of them were tiny little Sams.

More games with biodata. It wasn't hard to figure out what was happening here. The vault was using Sam's own biodata to create defences, as a way of protecting the mysterious Relic. She didn't know why the defences were so complicated, though. If Qixotl had wanted to get rid of intruders, he could have just put some kind of laser-screen around the casket and fried anyone who got too close.

But then again, there were a lot of alien species in the ziggurat, and some of them were probably laser-proof. So, if the defences turned your own biodata against you, they were bound to find something you were susceptible to. Yeah, that made sense. The vault knew every weakness Sam had. Even the babies... human beings were funny about babies, Sam knew that. Babies were supposed to be pure, innocent, lovable. Most humans would have had trouble fighting babies, they'd feel like they were committing a cardinal sin, however pig-ugly the sprogs were.

Something grabbed Sam's foot. She didn't know what. She fell, face-first, into the offal-flavoured undergrowth. Before she could even think about getting up again, she felt something hovering above her head, breathing cold air down her neck. She tried to turn onto her back, but whatever had snared her was holding onto her legs, winding itself around her thighs. She managed to squeeze out of its grip, eventually, but by then she was already cornered.

The thing hovering over her was baby-shaped, and its siblings were bobbing up and down around it, arranging themselves into some kind of attack formation. The babies floated down towards her face, their chubby little arms outstretched. Sam wondered if they'd developed teeth yet.

Homunculette had stopped struggling. Whatever the cultists had used to tie him up, it wasn't going to budge. At the training complex on Gallifrey XII, the War Cardinals had taught him the basics of escapology; generations of Time Lord renegades, he'd been told, had discovered that there was no skill in all the universe more important than the ability to get out of tight corners. Homumculette had been cynical at the time. Escapology, he'd thought, hadn't helped most of the Time Lords get off the original homeworld before it had been wiped.

He was even more cynical now. He lay on his side, on the floor of the anteroom, the two Faction Paradox lunatics standing guard over him. The man seemed intent on finding a reason to kick Homunculette in the stomach every few minutes, while the woman still looked as serene as ever.

The witch. Homunculette felt it burning up his nervous system again, the fury of the righteous, the memory of Marie's broken face. There was only room for one idea in his head right now, and the idea was revenge revenge. Everything else was background noise.

The male cultist kicked him once more, and Homunculette screamed at him in Old High Gallifreyan, but the shout seemed like nothing next to the howling of the birds outside the ziggurat.

'What are you going to do with him?' somebody asked. It was the human Colonel, Homunculette realised. The man was standing somewhere behind him.

Cousin Justine considered the question for a moment. 'We believe we should respect the beliefs of our host. We will leave judgement of Mr Homunculette to Mr Qixotl.'

'He's on his way,' said a new voice.

Homunculette wriggled around until his face pointed towards the doorway. Two individuals had entered the anteroom. One, the one who'd spoken, was the idiot with the curls and the laughable fashion sense. The other wasn't even humanoid, although it looked like it wanted to be. It was as tall as the average Gallifreyan, its flesh sculpted out of smooth white crystal. Its bulky torso filled most of the doorway, and two thick arms extended from the front of its body. One of them seemed to end in a weapon of some kind.

'A Kroton?' the witch-woman said.

'Shee-it,' smirked her companion.

The curly man bowed. 'May I present to you all, E-Kobalt-Prime of the Kroton Absolute. Fifth Lattice, apparently.' He stretched out a hand, as if to usher the Kroton into the room. 'I think you all should know, E-Kobalt's already called in the reinforcements. So please try to be polite.'

The crystal monstrosity shambled into the room, its head spinning stupidly on top of its body. Homunculette noticed that someone had scratched letters into the thin layer of dust on the floor in front of him. I'VE GOT TO ADMIT, I'M SURPRISED, said the Shift.

Kortez cleared his throat. 'On behalf of the people of Earth ' he began.

'We-are-read-y-to-be-gin-the-auction?' queried E-Kobalt, not waiting for the human to finish the speech. The Colonel looked slightly insulted.

Cousin Justine stepped forward. 'E-Kobalt-Prime. Faction Paradox welcomes you here, in the name of the Grandfather, and by the will of the Spirits.' The Kroton's head spun all the way around, as if searching for these Spirits it was being introduced to. 'Please excuse us, but we weren't expecting a being such as yourself. Your people aren't known to be time-active, and your empire is many millennia away from here. We understood you posessed only theoretical knowledge of the Spirits of Time.'

'The-time-corr-i-dor-to-this-loc-a-tion-was-op-ened-by-the-al-i-en-vess-el-I-int-er-cep-ted. The-War-spear-I-have-summ-oned-will-fol-low-the-same-corr-i-dor.'

'But even so. To find you interested in the Relic...'

'What she means is, n.o.body takes you seriously,' slurred Homunculette. 'We were expecting someone dangerous. The Cybermen or the Sontarans. Even the Voord are more frightening than you people.' The other Faction cultist sn.i.g.g.e.red at that, but it didn't stop him kicking Homunculette in the guts.

The man with the curls smiled. Homunculette got the feeling he was laughing at all of them. 'I can see we're all going to get along splendidly. Mr Qixotl's gone to shut off the alarms, by the way. Until he gets back, does anybody feel like a quick game of chess? I've got a pocket set with me, and I think I've got the hang of the way the horsey things move now.'

Bregman wasn't sure where the labyrinth had come from. The last thing she remembered, properly remembered, was the vault. The Relic had been behind her, and her own face had been staring at her from the buds of the flesh-plants. She vaguely recalled seeing the entrance to a tunnel somewhere nearby. She seemed to remember trampling through the flowers, crushing her own head under her boots as she'd made for the exit.

The walls of the labyrinth were smooth and fleshy, made of a substance that seemed almost transparent, if you stared at it hard enough. There were dark shapes moving on the other side of those walls. The architecture of the vault had crumbled, letting the maze grow up in its place. The floor was carpeted with rubble and bioma.s.s.

Another bunch of flowers exploded from the ground in front of Bregman. They were larger than the others she'd seen, the buds almost touching the ceiling, each stem the width of one of her thighs. She skidded to a halt, slipped, and fell onto her back. Half a dozen crude copies of her own head swung down at her, blinking in a dazed fashion.

Jesus. Did she really look like that? The faces were so bland, so lost-looking, so... stupid stupid. Dumb animal faces. Cows on the way to the slaughter-yard, hedgehogs ambling across motorways. Yeah, and wasn't that the truth? Lieutenant Kathleen Bregman, a proud example of the human race, the sentient cattle of the universe. Around here, even the furniture was smarter than she was.

The heads swung this way and that, taking in the labyrinth around them but not understanding the first thing about it. And they were so d.a.m.ned ugly. Deformed, even. Christ. How could she, how could any human being, ever face the world again after what she'd seen here in the City? How was she even supposed to pretend to be part of an intelligent species? Stupid. Like Homunculette had said. Too stupid to get off this planet. There was a st.i.tch in Bregman's side, a sick feeling in her gut. She stank of sweat, the stench of a primitive ape-creature with no control over its own biology. Ugly. Primitive. Useless.

The heads kept leering down at Bregman, reflecting every single one of her imperfections back at her. The floor trembled beneath her backbone, but she didn't bother getting up. There didn't seem much point trying to stay alive any longer. Not now she knew what she was really worth.

The dinosaur was still busy sawing the heads off the vestal virgins. That was a relief, anyway. Right now, it wouldn't have surprised Qixotl if the figures had jumped out of the tapestry and gone walkabout in the ziggurat. The security centre hadn't been touched since he'd been here with the Doctor, but somehow the place felt alien to him now, like an old friend who suddenly wasn't speaking to him any more.

Naturally, he'd lied to E-Kobalt. The toucans weren't screeching because of the s.p.a.ceship. The racket they were making was louder than a simple intruder alert. Something had activated the deeper defences of the ziggurat. Someone had reached the vault.

Mr Qixotl told the console to give him a visual scan of what was happening down on the lowest level. Immediately, the pixscreen was filled with an image Qixotl could only have described as disgusting. He squinted at it for a good half a minute before he realised what he was looking at. It was the interior of a human intestinal tract, blown up to absurd proportions.

He asked the console for an overview of the vault. Oh, right, now it made sense. Two of the humans had reached the Relic. How they'd got that far, Qixotl wasn't sure. Maybe it had been something to do with the corpse. The Doctor had a thing about humans, according to the old stories; something to do with his retroactive ancestry, apparently. The telepathic bits of his brain could have latched onto the humans, even after death. The stiff might have summoned them, sent out a psychic SOS, probably not even realising it was dead and therefore didn't actually need rescuing. But if the body could shut off most of the defences around it, just using its residual psychic ability... well, it was no wonder the Time Lords thought they could turn it into a weapon.

Even the corpse hadn't been able to shut down the core defences, though. Qixotl called up another visual. There she was, the UNISYC woman, being menaced by her own head, times six. Oddly, the heads were staring her out instead of attacking her.

Qixotl asked the console for a diagnostic. According to the figures on the pixscreen, the systems had a.n.a.lysed her biodata, and found her greatest weakness to be psychological, not physical. Specifically, she had an inferiority complex the size of the Crab Nebula. She was young, she was fit, she was healthy, but she thought thought she was a complete wreck on the verge of total bodily collapse. She had a bunch of appearance-related neuroses, too, which was only to be expected in a culture as media-aware as Earth's. The planet's TV transmissions were full of icon-images, Qixotl had noticed, cybernetically enhanced movie legends and smoother-than-life pop stars, all plastic surgery and computer airbrushing. That kind of thing always got ape-descendants a bit paranoid. she was a complete wreck on the verge of total bodily collapse. She had a bunch of appearance-related neuroses, too, which was only to be expected in a culture as media-aware as Earth's. The planet's TV transmissions were full of icon-images, Qixotl had noticed, cybernetically enhanced movie legends and smoother-than-life pop stars, all plastic surgery and computer airbrushing. That kind of thing always got ape-descendants a bit paranoid.

In light of all this, the systems had decided not to kill the UNISYC woman. Instead, they were bombarding her with stimuli designed to trigger an industrial-strength nervous breakdown. In short, the vault was driving her mad. Being trapped in a labyrinth based on the design of her own large intestine was all part of the process.

Mr Qixotl goaded the master console into giving him the low-down on the other human. It turned out to be the Doctor's little a.s.sistant. No surprises there, then.

The girl wasn't anywhere near as unstable as the UNISYC agent, so the vault was attacking her physically, growing malicious little antibodies from its bioma.s.s, hostile infant versions of the girl herself. As Qixotl watched, another biological unit was vomited out of the walls. He frowned when he saw the form the new antibody took. All the defences were supposed to be based on the victim's own biodata, but this one looked different, somehow. Did the girl have things in her biodata Qixotl hadn't detected before, or had there been another systems glitch?

Well, anyway. Soon, both the humans would be dead. Qixotl considered shutting down the defences and letting them out of the vault, but then, if he did that, he'd have to boot up the security systems from scratch, and that'd take all day. No. He'd let them snuff it down there, and if anyone asked, he'd say it was their own fault. Diplomacy be d.a.m.ned. Neither of the humans was important, anyhow. The UNISYC woman was only an attachment to Kortez, and if the girl was the Doctor's pet, he could easily get hold of another one. There were were nearly ten billion of them on this planet. nearly ten billion of them on this planet.

All in all, he had more important things to think about. The last of the bidders had arrived. The representatives would be getting impatient, and frankly, Mr Qixotl had run out of delaying tactics. At long last, it was time for the bidding to start.