The pilot was a young man by the name of Cash Baker, one of the wing of combat pilots Sri had gifted with neurological enhancements a year ago. She asked him how his modifications were bedding in, and he told her that everything was working just fine, he was on his way back to Adiena after meetings with engineers who were supervising the final stages of the refit of a freighter converted to a carrier for J-2 singleships. Sri cut him off when he began to eulogise the carrier's properties, told him that she was going to sleep out the trip.

The ability to fall asleep at will was a trivial cut she'd given herself in her salad days. She'd given it to Yamil Cho as well. They slept together side by side in their crash couches while the Uakti powered across three hundred and eighty thousand kilometres, woke at almost the same moment. They were swinging close around the Moon's dark and ravaged far side towards a swift dawn and Earthrise, and the pilot was gossiping with traffic control, guiding the shuttle in to a perfect landing on one of the pads north of the low tents and domes of Athena.

A rolligon ferried Sri and Yamil Cho past fields of vacuum organisms to the old research station where Sri had spent her apprenticeship. A string of low buildings covered by berms of dust and rock, it was now the cover for the facility deep underground. The rolligon drove past a gig and several tracked vehicles into a brightly lit garage. After the outer door shut and the garage had been pressurised, two women, slender black-haired identical twins dressed in red skinsuits, escorted Sri and her secretary to an express elevator that descended to the first level of the facility. This was where the superbright chimpanzees lived. Just as the research station was cover for them, so they were cover for the second level, where Oxbow's real secret was hidden.

General Arvam Peixoto was waiting for Sri in the conference room, standing at the wide armoured-glass picture window that looked out across the green arbours of the superbright chimps' habitat. The director of the facility, the chief of security, and the head of the research and development team were there too, bracketed by two more slender women in red skinsuits. Sri wondered who had cut them.

'Five,' Arvam said. He was dressed in a grey flight suit slashed with zippered pockets and his long white hair was done up in a ponytail. A pistol with a chequered steel grip rode his hip in a black leather holster. Saying, 'Can you believe it? Five. And they reached the surface, too.'

'Are any still alive?'

'The second layer of security got them all. But it was damned close. These monsters of yours are getting too damned smart.'

'I think you should tell me everything,' Sri said.

Arvam gestured to the director, Ernest Genlicht-Ho.

'They tunnelled out,' Genlicht-Ho said. 'Fortunately, the so-called deathstar satellite spotted them immediately, and took appropriate action.'

He called up video in the room's memo space. A panoramic view of the lightly cratered surface to the west of the research station zoomed in on a sudden geyser of dust that fell away to reveal five naked figures climbing out of a pit, each inside an inflated bubble of gold-tinted plastic. Views from various angles and distances showed a shuttle dropping towards the figures out of the black sky, the five golden bubbles bursting, collapsing over the figures inside as they thrashed and quietened and lay still, the shuttle swinging past low overhead, its motor still burning as it smashed into the ground and ripped a long trench across the plain.

Ernest Genlicht-Ho explained that the superbrights had infiltrated the security system, established a communications link with traffic control at Athena, and taken control of one of the shuttles. 'As for the escape itself, one of our subjects broke out during a routine medical check. The tranquilliser administered to him turned out to be distilled water. By the time we realised that the security system had been compromised, he'd killed two doctors and five wranglers, and had freed four of his siblings.'

The superbrights seemed to have accessed the security system by use of a quantum tunnelling device. It had transmitted data at a very low bit rate - the security chief believed that it had taken them more than six months to assemble the viral subpersonality that had taken control of the system's AI during the escape attempt - but the superbrights had had nothing but time. After they'd finally subverted the security system, they'd used it to gain access to the medical robots, swapping tranquilliser capsules for distilled-water placebos used in medical studies. The five who had broken out had used shaped explosive charges to tunnel their way through the containment perimeter and thirty metres of lunar regolith; the bubbles that had protected them from vacuum had been part of an experiment that one of them had been conducting with a new kind of memory plastic. They had been within ten seconds of reaching the shuttle when the security satellite had fried them with microwave bursts and killed the shuttle's AI.

'You have to admire the little buggers,' Arvam told Sri. 'They don't give up. Their first attempt, two of them bite out each other's throats, and a third almost gets free when the wranglers go to clean it up. Then they compromised the security AI and used that ultrasound gadget to make everyone in the facility as sick as dogs. Two of them actually broke into the garage before the wolves caught them. And now this. They got into the security AI again, even though I was assured that new firewalls and personality mirroring had made it impossible. That virus of theirs took down the wolves, too, which means that two who almost got away on the second attempt must have been in contact with the ones who stayed behind. Am I correct, Doctor Genlicht-Ho?'

'It appears so.' Ernest Genlicht-Ho's face was the colour of unsized paper. Beads of sweat stood out on his forehead. 'The first two sorties may not have not been separate incidents, as we thought, but part of the preparations for this attempt.'

'Tell her the rest,' Arvam Peixoto said.

Genlicht-Ho looked at the floor. 'There is a possibility that one or more of the wranglers gave them help.'

'More than a "possibility",' Arvam said. 'Someone called in that shuttle. They couldn't have known about such a thing, let alone accessed it.'

'With respect, they manufactured a neutrino backscattering device three years ago,' Genlicht-Ho said. 'It turned out to be quite profitable, actually, a form of deep radar with far greater range and resolution than anything commercially available. It is possible that they could have mapped an area around the station some twenty kilometres in diameter during its development. The spaceport falls comfortably within that footprint.'

'Perhaps they knew about shuttles. But they certainly did not know how to access one remotely. For that they would have needed help,' Arvam said, looking straight at Sri.

'Put me to the question, and you'll see that I had nothing to do with this,' Sri said, cold and angry and afraid. 'Question my secretary, too.'

'I don't doubt your loyalty,' Arvam said. 'As for these three, they are damn fools for allowing this to happen, but they are not traitors. That leaves the wranglers. None of them are ever allowed to leave level two, much less the facility, but it is possible that the superbrights turned one of them somehow, or made him into their puppet. Or perhaps one of them is a sleeper - an agent inserted when this facility was first set up. We're questioning everyone involved, of course.'

Arvam was smiling and his voice was even and pleasant, but his gaze was ice-cold. Sri's fear twisted a notch higher. She had seen him like this before, and was certain that he was planning to make an example of someone. If he tried to shoot her, or if he told his bodyguards to kill her, Yamil Cho would have to put them all down. And then, providing she could get out of the facility, she'd have to put into effect her plan to flee to the Outer System, no question about it . . .

Still smiling, Arvam asked Ernest Genlicht-Ho if he had any suggestions about moving forward from this.

'We should separate them from each other,' the director said. 'All of their escape attempts have required cooperation between several individuals. If they were isolated, it would greatly reduce their ability to formulate and execute a plan.'

'It sounds expensive,' Arvam said.

The chief of security agreed that it would indeed be very expensive.

'Unfortunately, given their ability to use ordinary laboratory equipment to communicate over great distances, it would be necessary to build individual facilities. Either in different parts of the Moon, or in orbit.'

'But the potential benefits are enormous,' the head of research and development said. He'd thrust his hands into the pockets of his smock to conceal their trembling. 'They have already produced the fusion motor, deep radar, the pulse rifle, a new type of polywater . . .'

'What do you think we should do?' Arvam said to Sri. 'You cut these little buggers. Can we keep hold of them?'

'It will be very difficult. They have learned too much. They have a deep desire to escape. There will be more attempts, and each will be more sophisticated than the last.'

The security chief quivered. 'With respect, sir, Dr Hong-Owen is quite right. On the one hand, we have to be one hundred per cent vigilant one hundred per cent of the time. On the other, all they have to do is wait until there is a lapse they can exploit.'

Arvam said pleasantly, 'So you're bound to fuck up again, is that it?'

'We are only human,' Ernest Genlicht-Ho said. 'And they are something more than human.'

Arvam looked at Sri. 'Tell me what to do.'

Sri was ready for the question. She'd been ready for it ever since she had heard about the code ten.

'Destroy them.'

'Right now?'

'They can't work in isolation. They are successful only when they work as a gestalt, but we can't contain that gestalt. So the experiment must end.'

'That's what I thought,' Arvam said, and drew his pistol and shot Ernest Genlicht-Ho twice in the chest. The security chief straightened his back and closed his eyes before Arvam shot him, but the head of research and development bolted towards the door and one of Arvam's bodyguards sprang on him like a cat and broke his neck. Sri stood as still as she could, Yamil Cho poised beside her, as Arvam holstered his pistol and said, 'Well, that's that.'

'Not quite,' Sri said. 'I must deal with the surviving superbrights.'

'Of course. And my people will deal with the wranglers, once we have established which one of them helped the superbrights, and why. What about the chimps?' Arvam said, turning to look out of the window.

Sri stepped up to join him. Near the top of a tree some ten metres away one of the chimps sprawled on its back in a platform woven from bent and broken branches. Its dark brown eyes gazing at infinity as its fingers spidered across a slate resting on its chest, conjuring a dense flow of symbols. Sri had created it and others like it from genome templates of the western common chimpanzee, Pan troglodytes verus. Cuts had forced the growth of fast, dense neuronal connections that massively boosted intelligence beyond the level of ordinary human genius, but the chimps had turned out to be a dead end. Those few which had not gone insane or committed suicide hammered out intricate flights of weird and highly complex mathematical reasoning as instinctively as breathing, but most of their work consisted of esoteric proofs of well-known theorems, and was of little interest to anyone apart from the research team that sifted a few useful nuggets from the reams of calculations. And those nuggets were growing rarer. The chimps were evolving away from conventional mathematics, spinning baroque fantasies that even the best human mathematicians had trouble connecting with reality.

Sri would mourn their passing, but their usefulness was at an end, and she felt only a small pang of sorrow when she told Arvam Peixoto, 'We don't need them any more, either.'

'Good. Now let's deal with the real problem.'

About forty people in the upper circles of the Peixoto family, including Oscar Finnegan Ramos, knew about the chimps, believing them to be the source of wondrous technological advances that in the last ten years had made the family the most powerful in Greater Brazil. But only the crew of Oxbow, Sri, her secretary, Arvam Peixoto, and six members of the family's inner council knew about level two, the real source of the near-magical technologies. That was where Sri and Arvam Peixoto went now, past robot sentries equipped with triple copies of hardened, hardwired and heavily shielded core processors, down a long moving-floor ramp, past more robot sentries and two of Arvam's red-clad bodyguards, into the secret within a secret.

The master surveillance room where shifts of wranglers usually worked around the clock was deserted except for a trio of robots balanced on their ball-drives. Memo spaces showed views of every room and corridor in the second level, views from every angle of the superbrights'

cage. It was a big sphere with soft plastic walls, cluttered with shelves and equipment racks, workbenches and immersion tanks, exercise machines, two closed-cycle toilets and a single shower unit. Sleeping bags hung like shed cocoons. In the beginning, after a brief two-year force-grown transition from birth to adulthood, fourteen superbrights had lived and worked there. Sri had cut them from human embryos, using techniques that she had developed while experimenting on the chimps, adding to the mix a form of low-scale autism so that, using behavioural cues, the superbrights could be trained to absorb new techniques and blocks of knowledge, and work with intense concentration on problems set them by their wranglers. They had evolved their own language, a shorthand of expressions and finger-shapes that conveyed complex ideas with astonishing rapidity; when they were all working on the same problem, they moved and worked with harmonious synchrony, as if engaged in an elegant and endless free-form dance.

Now nine of her brilliant children were dead, killed during various escape attempts, and the survivors were penned in one of the medical cells, surgically anaesthetised, awaiting their fate. Sri felt a mix of pride and sorrow. Proud because they had achieved so much in so short a space of time. Even the fierce and ruthless determination with which they had worked to escape was to be admired. Sorrowful because they had reached the inevitable end that she had forecast when she had first drawn up plans to create them.

She pressed a palm against a screen that checked her DNA and metabolic signature. She uploaded the necessary key into the system, then told Arvam that she'd like to see the superbrights one last time.

'I never before believed that you were sentimental,' he said. 'All right. Two of my people will take you.'

Sri couldn't enter the medical cell because its air was tainted with anaesthetic. All she could do was stand at the door and look through the judas. The five superbrights lay on pallets, memo spaces displaying trace readouts above their heads. They were androgyne neuters, naked, pale, hairless, and about a metre tall. Child-sized, but nothing like children, with broad chests, large heads and small, delicate limbs. Their faces were calm and still beneath asymmetrically swollen foreheads - Sri had discovered that the most stable personalities were obtained by selective stimulation of growth of the left cerebral hemisphere.

Although they had a strong familial resemblance, with close-set eyes and flat noses and small, down-curved mouths, she recognised each one and said goodbye to each in turn before activating the key and opening a vent connected to the vacuum of the lunar surface.

A pale mist distilled from the air and was quickly shredded and whisked away. The mouths of the sleepers gaped wide as they gasped for air; their chests rose and fell with rapid irregular convulsions and abruptly stopped moving; bloated tongues parted blue lips and swelled further and ruptured, spattering blood; blood burst from their nostrils and leaked from the corners of their eyes, boiling in the vacuum even as it streaked their pale skin. Trace readings flatlined.

The sleepers were dead. This part of Sri's life was over. She turned away, sorrow and self-pity swelling her heart.

'That was well done,' Arvam said. 'It reminds me that I should also thank you for the many hours of amusing material you sent to me after your little trip to Callisto.'

'I thought you had forgotten about it,' Sri said.

'Oh, I never forget a favour. Now, I want to see how your other children are doing. I drink we'll be needing them very soon. After all, the end of one chapter is always followed by the beginning of another, eh?'

5.

Father Aldos banged through the gymnasium's double doors, hurried past boys paired on green mats and thrusting and parrying with knives, and mounted the low platform at the end of the long room. He talked briefly with Father Solomon, then clapped twice to get the boys' attention.

Dave #8 bowed to his partner, Dave #15, who bowed to him, and they both turned to face front as all around them their brothers did the same, like a single movement reflected in a hall of mirrors.

'We have visitors,' Father Aldos said. His handsome cafe con leite face was darkly flushed, his gaze pinched and anxious. 'Important visitors. You will all now stand ready for inspection.'

The boys straightened their backs and raised their heavy practice knives in front of their faces. All of them bare-chested and barefoot, wearing only loose white trousers tied at waist and ankles. Plastic greaves strapped to their forearms. For several minutes nothing happened. Dave #8 stared past the blade of his knife at an imaginary point hung in the air a metre in front of him. Sweat cooled and dried on his chest and back, on his naked scalp. He was excited and apprehensive and was wondering if his brothers felt the same way. At last there was a bustle of activity at the edge of his vision. He cut his gaze to the left, saw that four strangers had appeared at the entrance to the gymnasium. Uniformed in black combat coveralls and visored helmets and combat boots, armed with short-barrelled carbines, they took up positions either side of the entrance as more people appeared. Two men and a woman, closely followed by Father Clarke and Father Ramez.

Dave #8's heart bumped inside his chest. The woman was the woman whose face sometimes appeared in one of the avatars: Sri Hong-Owen.

There was a faint stir in the boys' ranks as she moved past them to the low platform where Father Aldos and Father Solomon were waiting. She talked briefly with the two lectors and turned and studied the ranks of the boys. She was dressed in a long quilted coat that hung open over a knitted garment and quilted trousers and knee-length boots with ruffs of white fur around their tops. Her pale and naked scalp gleamed in the harsh light. Dave #8 felt his blood beat in his face as her sharp gaze moved over him.

The smaller of the two men who accompanied her was clearly the most dangerous. Slim and supple in a black shirt and black trousers, his posture relaxed but his gaze sharp and alert. The other man was much older, dressed in a grey flight suit with a big pistol holstered at his right hip. He had an air of confident authority, stepping to the edge of the platform, his voice ringing out across the room when he told the boys that he was General Arvam Peixoto.

'My family, the Peixoto family, owns the facility. Everything that happens in it is under my command. I am here today because your basic training is coming to an end. I know that will be hard for you to accept. You have been in training all your lives. In fact, it is the only life that you know. But training is not an end to itself. It is time now to put the skills you have learned here to the test.' The general paused, looking past the boys at the racks of weapons and equipment along the walls, then said, 'I see all manner of weapons here.'

After a moment, Father Solomon volunteered, 'We have trained them for every eventuality, General.'

'I see bows and arrows.'

'They are silent weapons and can carry a variety of payloads, from simple barbs to tethers or vials of nerve gas or explosive. Also, arrows will travel great distances in low gravity. And in the vacuum and zero gravity of true space, they will continue to fly without losing velocity until they strike their target. Also, practice increases hand-to-eye coordination-'

'And swords too,' the general said. 'Knives I can understand. Knives can be useful in close combat. Swords, though. In what kind of battle might swords be useful?'

'Again, hand-to-eye coordination-'

'It seems to me that you indulge these boys. You train them for everything, and as a result they are useful for nothing in particular. They are not focused.' The general turned to Sri Hong-Owen and said, 'How do you think we can help them focus?'

'Don't involve me in this,' she said.

'But these are your boys,' the general said. He was smiling, but it was only to show his teeth. 'Your creations. The flesh of your flesh, transformed by your skill and hard work. Surely you must have an opinion.'

Dave #8 was struck by a fierce and holy exultation. Dave #27, the wisest of his brothers, had been right all along. They were not Outers. No, they were weapons to be used against the Outers, and so they had been given the form of their enemy, but they were not doubly fallen. They were human. They could be redeemed. His joy surged up inside him. He had to bite the inside of his cheeks to stop himself shouting out and he was trembling from head to foot, and the brother standing in front of him, Dave #11, was trembling too.

'If you brought me here to prove something,' Sri Hong-Owen told the general, 'then do what you feel you must. Don't make it into a game.'

There was a brief silence. Father Clarke said, 'If this is a question of their prowess, if you would like a demonstration, I am sure that something can be arranged. They are skilled in all the weapons you see here. As well as several kinds of hand-to-hand combat, of course. It will take very little time to set up a demonstration of their prowess in any form of combat.'

The general turned his chill smile to the lector. 'How about knives?'

'Well, of course,' Father Clarke said. 'They were engaged in a training exercise in knife-fighting when you arrived. If you would like them to continue-'

'Who is the best?'

'At knife-fighting?'

'At everything. Your most apt pupil.'

'They are trained in a wide variety of techniques ... It is hard to say.'

'I'll make it easier,' the general said. 'Who is the one you would save, if you could save only one?'

'I don't quite follow you,' Father Clarke said. He was clutching his pectoral cross in his right hand, knuckles squeezed white.

'Number Eight,' Father Solomon said. 'If you must use one of them, use Number Eight.'

'Is he the one you would save out of all of them?' the general said. 'Or is he the first you would sacrifice, if you had to?'

'He is the best.'

Father Solomon looked as though he wanted to use his shock stick on the general.

'Let's see. Bring him to me.'

Father Solomon turned to face the boys and said, 'Number Eight. Step forward.'

Dave #8, his knife still raised in front of his face, took the regulation three paces off the edge of the green mat onto cold, polished concrete. He knew that Father Solomon had chosen him as a punishment, but he was determined to do whatever was asked of him to the best of his ability.

'There's no need for this,' Sri Hong-Owen said. 'Haven't I just now proved my loyalty?'

'That was no more than housekeeping,' the general said.

'The boys are loyal,' Father Clarke said. 'Utterly so. As are we, general.'