'So in all the essential details, nothing has happened to compromise the mission.'

Khouri wanted to strangle the woman, except it would have been like strangling a mirage. 'Has it occurred to you that they might have their own agenda? You know what Volyova said just before I was knocked out? She said I was the new Gunnery Officer. What do you suppose she meant by that?'

'It explains why they were looking for military experience in your background.'

'And what if I don't go along with her plans?' 'I doubt it matters to her.' The Mademoiselle stopped her strolling, adopting an expression of seriousness from her internal compendium of facial modes. 'They're Ultras, you see. Ultras have access to technologies considered taboo on colony worlds.'

'Such as?'

'Instruments for manipulating loyalty might be among them.'

'Well, thanks for giving me this important information well in advance.'

'Don't worry -- I always knew there was a chance of this.' The Mademoiselle paused and touched the side of her own head. 'I took precautions accordingly.'

'That's a relief.'

'The implant I put inside you will fabricate antigens for their neural medichines. More than that, it will also broadcast subliminal reinforcement messages into your subconscious mind. Volyova's loyalty therapies will be completely neutralised.'

'So why bother even telling me this is going to happen?'

'Because, dear girl, once Volyova begins the treatment, you'll have to let her think it's working.'

The descent took only a few minutes, the air-pressure and temperature stabilised at surface normal.

The shaft which the car descended was walled in diamond, ten metres wide. Occasionally there were recesses, stash-holes for equipment or small operations shacks, or switching points where two elevators could squeeze past one another before continuing their journeys. Servitors were working the diamond, extruding it in atomic-thickness filaments from spinnerettes. The filaments zipped neatly into place under the action of protein-sized molecular machines. Looking through the glass ceiling, the faintly translucent shaft seemed to reach towards infinity.

'Why didn't you tell me you'd found this?' Sylveste asked. 'You must have been here for months at the very least.'

'Let's just say your input wasn't critical,' Girardieau said, and then added, 'until now, that is.'

At the shaft's bottom, they exited into another corridor, silver-clad, cleaner and cooler than the one they had walked through at ground level. Windows along its length offered glimpses into a disarmingly large cavern filled with geodesic scaffolding and industrial structures. Sylveste was able to freezeframe the view with his eyes, then do some image-processing and expand the captured view when he was ten paces further along the corridor. For that he offered grudging thanks to Calvin.

What he saw was enough to quicken his heartbeat.

Now they pushed through a pair of armoured doors ghosted by security entoptics, writhing snakes which seemed to hiss and spit at the group. They trooped on through into an ante-room with another set of doors at the far end, flanked by militia. Girardieau waved them aside, then turned to Sylveste. The roundness of his eyes, the Pekinese aspect of his features, suddenly made him think of a painted Japanese devil on the point of belching fire.

'Now this,' Girardieau said, 'is where you either ask for your money back or stand in awed silence.'

'Impress me,' Sylveste said, with as much droll nonchalance as he could muster, despite his racing pulse and feverish internal excitement.

Girardieau opened the rear doors. They walked into a room half the size of the freight elevator, empty apart from a row of simple escritoires inlaid into the wall. A headset and wraparound mike lay on one of them, next to a compad displaying pencil-sketch engineering diagrams. The walls sloped outwards, the area of the ceiling greater than the floor. Combined with the huge glass windows set in three of the walls, it made Sylveste feel as if he was in the gondola of an airship, cruising under a starless night sky across an unnavigated ocean.

Girardieau killed the lights, enabling them to see what lay beyond the glass.

Floods swung from the roof of the chamber beyond, curving down towards the Amarantin object which lay below. It was emerging from one nearly sheer wall of the cave; a hemisphere of pure black, hemmed by gantries and geodesic scaffolding. Scabrous lumps of hardened magma still clung to it, yet across the large areas where the magma had been chipped away, the thing was as smooth and dark as obsidian. The underlying shape was spherical; at least four hundred metres wide, although more than half still lay entombed.

'You know who made this?' Girardieau said, finally whispering. He did not wait for an answer: 'It's older than human language, but my goddamn wedding ring has more scratches on it.'

Girardieau led the party back to the elevator shaft for the final short descent down to the operations floor of the hollowed-out chamber. The ride lasted no more than thirty seconds, but for Sylveste it seemed like a grindingly slow Homeric odyssey. The object felt like his own personal prize; as hard-won as if he had unearthed it with his own bloodied fingernails. It loomed over them now, its curved, rock-encrusted side jutting unsupported into the air. There was a faint groove scored around the object, running obliquely from one side to the other. It looked like little more than a shallow hairline fracture from where he was, but it was a metre or so wide, and probably just as deep.

Girardieau led them into the nearest chock: a concrete structure with its own inner rooms and operations levels abutting the object. Inside they took another elevator, rising up through the building into the haze of scaffolding which erupted from it. Sylveste's stomach crawled with conflicting impulses of claustro- and agoraphobia. He felt hemmed in by the unthinkable megatonnes of rock looming hundreds of metres over his head, while simultaneously racked with vertigo as they ascended the scaffolding high up the side of the object.

Small shacks and equipment huts floated in the geodesic framework. The lift connected with one of these structures and they trooped out into a complex of rooms still abuzz with the afterhum of recently curtailed activity. All the warning signs and notices were decals or painted, the area too makeshift for entoptic generators.

They walked over a tremoring girderwork bridge which extended through a loom of scaffolding towards the black skin of the Amarantin object. They were halfway up the object's height, level with the groove. The object no longer seemed spherical; they were too close for that. It was a single black wall blocking their progress, as vast and depthless as the view of Lascaille's Shroud he remembered after he had travelled from Spindrift. They walked onwards, until the bridge took them into the groove.

The path immediately swung to the right. On three sides -- to the left, and above and below -- they were hemmed in by the eerily unmarked black substance of the artefact. They walked on a trelliswork path fixed to the underlying floor via suction pads, since the alien material was nearly frictionless. To the right was a waist-high safety railing and then several hundred metres of nothing.

Every five or six metres on the inside wall was a lamp, attached via epoxy pads, and every twenty or so metres was a panel marked with cryptic symbols.

They continued along the steep incline of the groove for three or four minutes until Girardieau brought them to a halt. The place where they had arrived was a tangled nexus of power lines, lamps and communications consoles. The left-hand wall of the groove folded inwards here.

'Took us weeks to find the way in,' Girardieau said. 'Originally the trench was plugged by basalt.

It was only after we'd chipped it all out that we found this one place where the basalt seemed to continue inwards, as if it were plugging some kind of radial tunnel which emerged in the trench.'

'You've been busy little beavers, I can see.'

'Digging it out was hard work,' Girardieau said. 'Excavating the trench was easy by comparison, but here we had to drill and remove material through the same tiny hole. Some of us wanted to use boser torches to cut a few secondary tunnels in to make the job easier, but we never went that far.

And our mineral-tipped drills couldn't touch the stuff.'

Sylveste's scientific curiosity momentarily beat his urge to belittle Girardieau's attempts at impressing him. 'You know what this material is?' 'Basically carbon, with some iron and niobium and a few rare metals as trace elements. But we don't know the structure. It's not simply some allotropic form of diamond we haven't invented yet, or even hyperdiamond. Maybe the top few tenths of a millimetre are close to diamond, but the stuff seems to undergo some kind of complex lattice transformation deeper down. The ultimate form -- far deeper than we've yet sampled -- may not even be a true crystal at all. It could be that the lattice breaks up into trillions of carbon-heavy macromolecules, locked together in a co-acting mass.

Sometimes these molecules seem to work their way to the surface along lattice flaws, which is the only time we see them.'

'You're talking as if it's purposeful.'

'Maybe it is. Maybe the molecules are like little enzymes tooled-up to repair the diamond crust when it becomes damaged.' He shrugged. 'But we've never isolated one of the macromolecules, or at least not in a stable form. They seem to lose coherence as soon as they're removed from the lattice. They fall apart before we can get a look inside them.'

'What you're describing,' Sylveste said, 'sounds very much like a form of molecular technology.'

Girardieau smiled at Sylveste, seeming to acknowledge the private game in which they were enmeshed.

'Except we know that the Amarantin were far too primitive for such a thing.'

'Of course.'

'Of course.' Girardieau smiled again, only this time to the group as a whole. 'Shall we forge inwards?'

Navigating the tunnel system which led from the groove was trickier than Sylveste had at first imagined. He had assumed that the radial tunnel would continue inwards for the necessary distance to traverse the shell of the object, and they would then enter the thing's hollow interior. But it was not like that at all. The thing was a deliberate labyrinth. The path did progress radially, for perhaps ten metres, but then it jerked to the left and soon branched into multiple tunnel systems. The routes were colour-coded with adhesive markers, but the coding system was too cryptic to make much sense to Sylveste. Within five minutes he was thoroughly disorientated, though he had the suspicion that they had not strayed very deep into the object. It was as if the tunnel system was the work of a demented maggot which preferred the part of the apple immediately under the skin. Eventually, however, they crossed what seemed to be a regular fissure in the fabric of the object. Girardieau explained that the thing was structured in a series of concentric shells. They continued to worm their way through another confusing tunnel system while Girardieau regaled them with dubious stories about the initial exploration of the object.

They had known about it for two years -- ever since Sylveste had drawn Pascale's attention to the oddity of the obelisk's burial sequence. Excavating the chamber had taken most of that time, detailed study of the object's warrenlike interior only happening in the last few months. There had been a few deaths in those early days. Nothing mysterious, it eventually transpired -- just teams getting lost in unmapped sections of the labyrinth and stumbling into vertical shafts in the tunnel system where the safety flooring had not yet been fixed. One worker had starved to death when she ventured too far without laying a breadcrumb trail behind her -- servitors found her two weeks after she went missing. She had been wandering in a series of doodle-like circles, at times only a few minutes from the safe zones.

Progress through the final concentric shell was slower and more deliberate than the four they traversed before it. They worked downwards, eventually reaching a gratifyingly horizontal stretch of tunnel, the far end of which was milky with light.

Girardieau spoke to his sleeve and the light dimmed.

They moved on in semi-darkness. Gradually their breathing ceased to echo from the walls as the confining space opened out. The only sound came from the laboured purring of nearby air pumps.

'Hold on,' Girardieau said. 'Here it comes.' Sylveste steeled himself for the inevitable disorientation when the lights returned. For once he did not mind Girardieau's theatrics. It permitted him a sense of discovery, albeit at second hand. Of course, he alone understood this surrogacy for what it was. But he did not begrudge the others the moment. That would have been churlish, for after all, they would never know what true discovery felt like. He almost pitied them, though in that moment the sight revealed in the lights purged all normal thought.

It was an alien city.

SIX.

En Route to Delta Pavonis, 2546

'I expect,' Volyova said, 'that you're one of those otherwise rational people who pride themselves on not believing in ghosts.'

Khouri looked at her, frowning slightly. Volyova had known from the outset that the woman was no fool, but it was still interesting to see how she reacted to the question.

'Ghosts, Triumvir? You can't be serious.'

'One thing you'll quickly learn about me,' Volyova said, 'is that I'm very seldom anything other than completely serious.' And then she indicated the door at which they had arrived, set unobtrusively into one rusty-red interior wall of the ship. The door was of heavy construction, a stylised drawing of a spider discernible through layers of corrosion and staining. 'Go ahead. I'll be right behind you.'

Khouri did as she was told without hesitation. Volyova was satisfied. In the three weeks since the woman had been snared -- or recruited, if one wanted to be polite about it -- Volyova had administered a complex regimen of loyalty-altering therapies. The treatment was almost complete, apart from the top-up doses which would continue indefinitely. Soon the woman's loyalty would be so strongly instilled that it would transcend mere obedience and become an animating compulsion, a principle to which she could no more fail to adhere than a fish could choose to stop breathing water. Taken to an extreme which Volyova hoped would prove unnecessary, Khouri could be made not only to desire to do the crew's will, but to love them for giving her the chance. But Volyova would relent before she programmed the woman that deeply. After her less than fruitful experiences with Nagorny, she was wary of creating another unquestioning guinea pig. It would not displease her if Khouri retained a trace of resentment.

Volyova did as she had promised, following Khouri into the door. The recruit had halted a few metres beyond the threshold, realising that there was no way to go further.

Volyova sealed the great iron iris of a door behind them.

'Where are we, Triumvir?'

'In a little private retreat of my own,' Volyova said. She spoke into her bracelet and made a light come on, but the interior remained shadowy. The room was shaped like a fat torpedo, twice as long as it was wide. The interior was sumptuously outfitted, with four scarlet-cushioned seats installed on the floor, next to each other, and space for another two behind, though nothing remained but their anchor-points. Where they were not upholstered in cushioned velvet, the room's brass-ribbed walls were curved and glossily dark, as if made of obsidian or black marble. There was a console of black ebony, attached to the armrest of the front seat in which Volyova now sat. She folded down the console, familiarising herself with the inset dials and controls, all of which were tooled in brass or copper, with elaborately inscribed labels, offset by flowered curlicues of differently inlaid woods and ivories. Not that it took much familiarising, since she visited the spider-room with reasonable regularity, but she enjoyed the tactile pleasure of stroking her fingertips across the board.

'I suggest you sit down,' she said. 'We're about to move.'

Khouri obeyed, sitting next to Volyova, who threw a number of ivory-handled switches, watching some of the dials on the panel light up with roseate glows, their needles quivering as power entered the spider-room's circuits. She extracted a certain sadistic pleasure in observing Khouri's disorientation, for the woman clearly had no idea where she was in the ship, nor what was about to happen. There were clunking sounds, and a sudden shifting, as if the room were a lifeboat which had just come adrift from a mother vessel.

'We're moving,' Khouri diagnosed. 'What is this -- some kind of luxury elevator for the Triumvirate?'

'Nothing so decadent. We're in an old shaft which leads to the outer hull.' 'You need a room just to take you to the hull?' Some of Khouri's scornful disregard for the niceties of Ultra life was coming to the fore again. Volyova liked that, perversely. It convinced her that the loyalty therapies had not destroyed the woman's personality, only redirected it.

'We're not just going to the hull,' Volyova said. 'Otherwise we'd walk.'

The motion was smooth now, but there were still occasional clunks as airlocks and traction systems assisted their passage. The shaft walls remained utterly black, but -- Volyova knew -- all that was about to change. Meanwhile, she watched Khouri, trying to guess whether the woman was scared or merely curious. If she had sense she would have realised by now that Volyova had invested too much time in her simply to kill her -- but on the other hand, the woman's military training on Sky's Edge must have taught her to take absolutely nothing for granted.

Her appearance had changed considerably since her recruitment, but little of that was due to the therapies. Her hair had always been short, but now it was absent entirely. Only up close was the peachy fuzz of regrowth visible. Her skull was quilted with fine, salmon-coloured scars. Those were the incision marks where Volyova had opened her head in order to emplace the implants which had formerly resided in Boris Nagorny.

There had been other surgical procedures, too. Khouri's body was peppered with shrapnel from her soldiering days, in addition to the almost invisibly healed scars of beam-weapon or projectile impact points. Some of the shrapnel shards lay deep -- too deep, it seemed, for the Sky's Edge medics to retrieve. And for the most part they would have caused her no harm, for they were biologically-inert composites not situated close to any vital organs. But the medics had been sloppy, too. Near the surface, dotted under Khouri's skin, Volyova found a few shards they really should have removed. She did it for them, examining each in turn before placing it in her lab. All but one of the shards would have caused no problems to her systems; non-metallic composites which could not interfere with the sensitive induction fields of the gunnery's interface machinery. But she catalogued and stored them anyway. The metal shard she frowned at, cursing the medics'

procedures, and then laid it next to the rest.

That had been messy work, but not nearly as bad as the neural work. For centuries, the commonest forms of implant had either been grown in situ or were designed to self-insert painlessly via existing orifices, but such procedures could not be applied to the unique and delicate gunnery interface implants. The only way to get them in or out was with a bone-saw, scalpel and a lot of mopping up afterwards. It had been doubly awkward because of the routine implants already resting in Khouri's skull, but after giving them a cursory examination Volyova had seen no reason to remove them. Had she done so, she would sooner or later have had to re-implant very similar devices just so Khouri could function normally beyond the gunnery. The implants had grafted well, and within a day -- with Khouri unconscious -- Volyova had placed her in the gunnery seat and verified that the ship was able to talk to her implants and vice versa. Further testing had to wait until the loyalty therapies were complete. That would mainly be done while the rest of the crew were asleep.

Caution: that was Volyova's current watchword. It was incaution that had resulted in the whole unpleasantness with Nagorny.

She would not make that mistake again.

'Why do I get the idea this is some kind of test?' Khouri said.

'It isn't. It's just----' Volyova waved a hand dismissively. 'Indulge me, will you? It's not much to ask.'

'How do I oblige -- by claiming to see ghosts?'

'Not by seeing them, Khouri, no. By hearing them.'

A light was visible now, beyond the black walls of the moving room. Of course, the walls were nothing but glass, and until that moment they had been surrounded only by the unlit metal of the shaft in which the room rested. But now illumination was shining from the shaft's approaching end.

The rest of the short journey took place in silence. The room pushed itself towards the light, until the chill blue luminance was flooding in from all angles. Then the room pushed itself beyond the hull.

Khouri upped from her seat and went to the glass, edging towards it with trepidation. The glass was, of course, hyperdiamond, and there was no danger that it would shatter or that Khouri would stumble and plunge through it. But it looked ridiculously thin and brittle, and the human mind was able to take only so many things on trust. Looking laterally, she would have seen the articulated spider-legs, eight of them, anchoring the room to the exterior hull of the ship. She would have understood why Volyova called this place the spider-room.

'I don't know who or what built it,' Volyova said. 'My guess is that they installed it when the ship itself was constructed, or when it was due to change hands, assuming anyone could ever afford to buy it. I think this room was a very elaborate ploy for impressing potential clients -- hence the general level of luxury.'

'Someone used it to make a sales pitch?'

'It makes a kind of sense -- assuming one has any need in the first place to actually be outside a vessel like this. If the ship's under thrust, then any observation pod sent outside also has to match that level of thrust, or else it gets left behind. No problem if that pod's just a camera system, but as soon as you put people aboard it it gets a lot more complicated; someone actually has to fly the damned thing, or at the very least know how to program the autopilot to do what you want. The spider-room avoids that difficulty by physically attaching itself to the ship. It's child's play to operate; just like crawling around on all-eights.'

'What happens if...'

'It loses its grip? Well, it's never happened -- even if it did, the room has various magnetic and hull-piercing grapples it can deploy; and even if those failed -- which they wouldn't, I assure you -- the room can propel itself independently; certainly for long enough to catch up with the ship. And even if that failed...' Volyova paused. 'Well, if that failed, I'd consider having a word with my deity- of-choice.'

Although Volyova had never taken the room more than a few hundred metres from its exit point on the hull, it would have been possible to crawl all around the ship. Not necessarily wise, however, for at relativistic speed the ship pushed through a blizzard of radiation which was normally screened by the hull insulation. The spider-room's thin walls only shielded a fraction of the flux, lending the whole exercise of being outside an odd and hazardous glamour.

The spider-room was her little secret; it was absent from the major blueprints, and to the best of her knowledge none of the others knew anything about it at all. In an ideal world, she would have kept it that way, but the problems with the gunnery had forced her into some necessary indiscretions. Even given the state of the ship's decay, Sajaki's network of surveillance devices was extensive, leaving the spider-room as one of the few places where Volyova could guarantee absolute privacy when she needed to discuss something sensitive with one of her recruits; something that she did not want the other Triumvirs to know about. She had been forced to reveal the spider-room to Nagorny so that she could talk with him frankly about the Sun Stealer problem, and for months -- as his condition deteriorated -- she had regretted that decision, always fearful that he would reveal the room's existence to Sajaki. But she need not have worried. By the end, Nagorny had been far too occupied with his nightmares to indulge in any subtleties of shipboard politick.

Now he had taken the secret to his grave and for the time being Volyova had been able to sleep easy, safe in the knowledge that her sanctuary was not about to be betrayed. Perhaps what she was doing now was an error she would later regret -- she had certainly sworn to herself not to violate the room's secrecy again -- but as always, current circumstances had forced her to amend an earlier decision. There was something she needed to discuss with Khouri; the ghosts were merely a pretext so that Khouri would not become overly suspicious of Volyova's deeper motives.

'I'm not seeing any ghosts yet,' the recruit said.

'You'll see, or rather hear them, shortly,' Volyova said.

The Triumvir was acting oddly, Khouri thought. More than once she had hinted that this room was her private retreat aboard the ship, and that the others -- Sajaki, Hegazi, and the other two women -- were not even aware that it existed. It seemed strange indeed that Volyova was prepared to reveal the room to Khouri so soon in their working relationship. Volyova was a solitary, obsessive figure, even aboard a ship crewed by militaristic chimerics -- not someone with a natural instinct for trustfulness, Khouri would have thought. Volyova was going through the motions of friendliness towards her, but there was something artificial about all her efforts... they were too planned, too lacking in anything resembling spontaneity. When Volyova made some kind of friendly overture to Khouri -- a piece of smalltalk, shipboard gossip or a joke -- there was always the feeling that Volyova had spent hours rehearsing, hoping she would sound off-the-cuff. Khouri had known people like that in the military; they seemed genuine at first, but they were usually the ones who turned out to be foreign spies or intelligence-gathering stooges from high command.

Volyova was doing her best to act casually about the whole spider-room business, but it was obvious to Khouri that the ghost thing was not all that it appeared. A number of disquieting thoughts struck Khouri, prime among them the idea that perhaps Volyova had brought her to this room with no intention of her ever leaving... alive, anyway.