Alisha. You grew up in that?

Up here, he still needed his respmask. Xavier Spalding preferred to keep his peregrinating house inside the hypozone. How best to signal the man?

But steel maws clanged open, and a curled-up rampway unfurled, like an unrolled carpet constructed of clanking iron. Roger directed the slickbike upwards, and it slid up the metal on its flowbelly, and squelched to a halt inside an entrance hall.

Steel decking, copper-and-steel chandeliers encrusted with spikes, and a floating glass arrow that trembled when he looked at it: that was all he saw.

‘I understand.’ He dismounted from the slickbike. ‘Carry on.’

The arrow moved and he followed, along a metal corridor ending in a door that split into a thousand razor-edged leaves and drew apart. Beyond, a silver door shivered into a mass of interlocking penrose tiles that folded back, like a snowdrift in strong wind.

Inside, the massive lounge was black and grey, touched with metallic purple. A shaven-headed man - Xavier Spalding - sat on a silver couch. Three steel eagles watched from perches, their heads turning to track Roger’s advance. One of them clashed its metal feathers; another opened and closed its angular steel beak.

‘They won’t attack,’ said Xavier.

‘But they could.’

‘If it were necessary. Clearly, we’re on the same side, Roger.’

‘What makes you say that?’

‘I may not be a Luculentus, but I have a measure of success, and many friends. You know how social networking follows an inverse-power relationship, I presume.’

‘There are many people with few acquaintances, and few people with many acquaintances, and it’s a straight-line relationship. ’ Roger decided this was a test. ‘Like the first internet, if you know your Terran history.’

The test was not to get annoyed at being asked what every child should know. If there are a million servers with a certain number of connections, then there might be half a million servers with double that number of connections, in a scale-free network. Or some similar inverse relationship.

‘A small number of nodes with a vast number of links,’ said Xavier. ‘Just so.’

‘Mathematically, you can’t define a meaningful average. Strategically, such networks are robust against random attacks, vulnerable to directed assaults. The original internet took twenty minutes to die, and it’s surprising it lasted that long.’

Xavier stared, picking up the implication: he was a vulnerable target.

‘I can see why my daughter likes you. Sit down, Mr Blackstone.’

‘Thank you. So you’re a primary node in a social network, are you, sir?’

‘Call me Xavier. So yes, Roger, I have a lot of friends.’

‘Or allies?’ The metal chair he selected was hard-looking, but felt comfortable. ‘Business acquaintances?’

‘Some of them are true friends. So I know, because of my acquaintances, that a mu-space ship burst into the open just above ground level, right in front of a house occupied by the Blackstone family. So where is it now?’

‘Where’s what?’

‘Your father’s ship. I’m assuming it’s your father’s, since he was clearly the major spy. Or have I got that wrong?’

This was not what Roger was here for.

‘It’s in another universe and they’re not coming back, that’s all, sir. Xavier.’

‘Ah.’ Xavier glanced at one of his steel eagles. ‘I see.’

‘Look, it’s Alisha I came to—’

‘Your parents fled, while SatScan thinks all three of you did. I’m guessing a smartmiasma was involved. So the peacekeepers think you’re offplanet for good, I take it.’

‘I don’t know.’

‘But you made your way here without problems.’

‘Not without—’ Roger thought about it. ‘If they were actively hunting me, I wouldn’t have got here as I did.’

Thanks, Dad.

Still looking out for his son, even as he ran for his ship - that was Dad.

‘Superintendent Sunadomari,’ he added, ‘knows you warned Dad, and gave him what he needed to shield against the scanners.’

‘Yes, and no one’s brought charges yet. Either Sunadomari is busy with more urgent affairs, or he intends to keep this knowledge as leverage. A primary social node is a useful asset for him to obtain, don’t you think?’

‘Er, yes.’

‘But then to protect me, to keep me useful, he has to be my friend also. Isn’t it interesting how that works out?’

Roger wanted to yell, but he made his voice soften.

‘It’s Alisha we need to be—’

But one of the steel eagles turned its head, and its eyes flashed yellow.

‘Interesting.’ Xavier’s smartlenses shone for a second. ‘You have access to the house. The student house on campus.’

‘I live there. Er . . .’

He used to. Where he lived now, that was undefined. Everyday life was in suspension.

‘Quite. So between your authorization and my resources, we can poll the system and trawl the logs. Alisha was in the house last night - she called me late - but this morning she’s gone.’

‘And she’s off Skein.’

‘My . . . friends . . . have been looking, unofficially. No sign in public.’

‘What if you make it official?’

‘A young woman is off Skein for a few hours. You think that will launch a high-priority surveillance sweep?’

‘I . . .’ Roger forced an exhalation. ‘You should talk to Superintendent Sunadomari.’

‘That’s right, and I will. But after you’ve gone.’

‘What do you mean?’

‘You’re a Pilot, and that comes with certain abilities. And you care about Alisha.’

‘So?’

‘My friends here’ - Xavier nodded, and three steel eagles rattled their wings - ‘can maintain line-of-sight tightbeam. You access the house from somewhere on campus, and they’ll relay the whole session via here.’

‘I don’t—’

‘This room will appear to be the point of origin for the signal.’

‘Oh.’

‘So if our peacekeeper friends are surprised by your continued presence on Fulgor, and decide they’d like to chat, they’ll think you’re with me, not in the city.’

‘And Sunadomari?’

‘Take one of my flyers, get to campus, interrogate the student house. Then I’ll call Sunadomari.’

‘While other peacekeepers are maybe already descending on this place?’ Roger gestured around the black-and-grey room. ‘Are you going to hold them off by force?’

‘I could, but that isn’t the way.’

A vertical steel cylinder was rotating to reveal an opening.

‘Lift-tube,’ Xavier went on. ‘It’ll take you to the flyer bay. The white flyer is ready to go.’

‘What if we’re already under full surveillance?’

‘Then it doesn’t matter what we do.’

‘I’m not sure we’re doing the—’

‘Get going, son. We need to find Alisha.’

Roger felt light-headed as he pushed himself up from the chair, realized he had eaten nothing, then pushed the feeling away. The lift-tube was waiting for him.

Sunadomari, in his flyer with two of Helen Eisberg’s tac troopers, could not wait to reach the Via Lucis Institute in reality. There were things he did not want to say, even in Skein, not until he was deep inside the physical as well as Skeinware barriers available to LuxPrime’s senior people. But he needed to talk to someone now.

In Skein, a Luculentus with golden headgear smiled at him.

‘Keinosuke Sunadomari, and you’re on your way here in person.’

‘Hsiu Li-Cheng, I certainly am.’

They used in-Skein audio, zipblips of sound, compressing sentences to millisecond-duration.

‘This can’t wait. Can you ensure we’re not being eavesdropped on?’

‘Excuse me, this is Skein.’

‘Assume you had a rogue Skein designer, with full knowledge.’

‘That’s not—All right, we’re secured.’

Neither of them made any attempt to create in-Skein images of themselves matching the spoken words; but Li-Cheng caused his visual representation to raise one eyebrow - a thousand times faster than reality.