‘Would you write up your thinking for the others to follow, please?’

‘Sure, Dr Helsen.’

‘Good. What I’d like all of you to do is construct a critique of the Founding Charter’s Assumption 17. Of course you’ll have done it years ago in school; what I’m looking for is an in-depth revisiting based on the knowledge you have gained since then.’

Alisha was frowning, and Roger took a moment to wonder why. The appearance of turbulence and other phase transitions in the Cyclone Lab just now - perhaps there had been a reason for Helsen’s showing them that, a hint in how to approach their analysis of Assumption 17: A surveilled society is a safe society.

‘For the rest of the afternoon,’ continued Helsen, ‘I’d like you to construct a simulation of an Earth city from the 1920s. Choose the city now, among yourselves.’

Then she turned away and stared across the plaza, either lost in thought or deep in Skein - as deep as an ordinary human could go, at any rate.

Rick gestured a real-image holo into being: an Earth globe floating above the tabletop.

‘Shanghai,’ he said. ‘An interesting mix of influences, with representatives of all the global powers of later centuries there. Plus lots of sex and violence.’

‘What about Paris?’ Stef pointed at the globe and a glowing spot appeared. ‘Centre of fashion and philosophy, what more could you want?’

Trudi’s smartlenses went opaque as she immersed herself in data, then cleared.

‘Chicago would be better, Rick, if you’re after bloody violence. ’

‘No, Shanghai. I mean, come on—’

Alisha’s voice was authoritative: ‘I nominate Roger to choose.’

‘Excuse me?’

‘Seconded,’ said Trudi, as Angela nodded.

Rick opened his mouth, but Alisha tilted her head toward Helsen and said: ‘A quick decision is in order, don’t you think?’

‘Then I agree.’ Rick grinned. ‘So I’m not going to suggest you choose Shanghai now, Roger.’

‘I’m glad you’re not suggesting that.’ Roger took control of the holo globe, expanding it and bringing it closer. ‘All right, let’s see.’

As he ran his hand across the surface, major cities flared, their names revealed in glowing white script: Budapest, Constantinople, Harare. Then he moved back up to western Europe, and his forefinger hovered over Berlin.

‘Is that your choice?’ said Rick.

‘Maybe.’ Then Roger’s hand drifted and he pressed down, pointing with forefinger and hooked thumb, the standard selection gesture. ‘This one.’

The city name glowed scarlet - Zürich - before fading back to white.

‘We’ve chosen, Dr Helsen,’ said Alisha.

‘Good.’ Helsen turned, her smartlenses opaque, then clearing. ‘So you’ve chosen Zürich, Mr Blackstone.’

‘Uh, yes, Doctor.’

‘I wonder you didn’t select Berlin.’

He tried to control his flinch, but a microgesture motion at the corner of Helsen’s mouth implied that she had read him perfectly. But why did it matter? Thinking back, he could not identify any covert commands in her earlier dialogue, unlike Rick with his deliberately obvious instruction regarding Shanghai. So how could she know that Berlin had tempted him? He didn’t even know why it had seemed to pull at his hand.

It wasn’t as if Earth history was even a favourite subject. He had studied it only because he had to.

Something seemed to shift beyond the edge of his vision, and he tried not to yell. Again, there was - perhaps - the tiniest twitch of Helsen’s mouth.

Have I failed a test? Or passed one?

Sour fear rose inside him. And now Alisha was staring. It was bad enough being psyched out by one person, but did they have to gang up on him?

‘I’ll see you in my teaching room tomorrow morning,’ said Helsen. ‘Seven fifteen, everyone.’

‘Yes, Doctor.’

‘Doctor.’

‘Ma’am . . . Uh, Doctor.’

Helsen was the first to leave, descending the quickglass stalk on a single-person flowdisk. Then the others drifted away, while Roger remained staring down at the plaza. He watched as Helsen reached ground level and walked away.

Just as she turned out of sight, black shards flickered in the air, twisted impossibly and were gone.

Is this a test?

But why would he feel such revulsion? This made no sense. Maybe Dad could explain - but he was facilitating those negotiations today, and besides, the point of going to college instead of studying virtually was to gain some adult independence, to strengthen the psychosocial skills that would let him make a career in the competitive world around him.

Except I’m not like other people.

He didn’t even know what he was. Perhaps he—

‘Interesting choice, Roger.’

He jumped.

‘Uh, Alisha. Um, thanks for having confidence in me.’

‘What do you mean?’

‘Voting for me to choose, of course.’

‘You thought that was a compliment, picking the quiet one?’

‘I - don’t know.’

‘That’s interesting.’

She broke eye contact, then walked toward the nearest flowdisk without a glance back at him. He could only stand watching as she descended, then walked off in the opposite direction to Helsen. The other students were already gone, including Rick, who had seemed so sociable.

‘So this is going well,’ he said to the empty balcony.

Then the tabletop spoke up.

‘The bill for seven drinks is outstanding. Do you wish to pay now?’

He sighed.

‘All right,’ he said.

In the evening, Rick suggested they play cops and robbers.

‘Excuse me?’ said Stef. ‘Are you serious?’

‘When you can’t tell the difference between avatars and in-scenario characters, it can be sort of fun.’

‘Then we should’ve chosen Chicago,’ said Trudi. ‘Shouldn’t you, Roger?’

‘I have no idea. My brain is dead.’

‘So you need some stimulation.’ Rick looked around the group. ‘Agreed?’

Around them the walls glowed soft pastels, while couches and chairs to individual taste had morphed from the floor. This was the communal lounge of their house, and their work on the Zürich simulation was finished. At least, none of them wanted to do any more.

‘Why not?’ said Stef.

Within two minutes, all six of them were standing in their own forms in a cobbled street on a foggy winter afternoon, their surroundings lit by hissing gaslamps. There were pedestrians - men in frock coats, women in bustling dresses that covered their ankles - none of whom saw the students. Some of the passers-by were speaking, their words translated but their tonality rendered with historical accuracy, along with their speed of movement.

‘They’re so slow,’ said Trudi. ‘The way they walk, and especially the way they talk. Do you think the records are really correct?’

‘After verification by twenty-two independent and loosely dependent methods,’ answered Alisha, ‘the analyses are trustworthy enough.’

Rick looked at Roger and raised an eyebrow. Clearly the group’s Luculenta-to-be was Alisha. Her expression was tightening, no doubt understanding their silent communication and not liking it.

‘Why don’t you three’ - her gesture passed across Rick, Roger and Trude - ‘commit some crime, while Stef, Angela and I take you down?’

‘That’s hardly specific,’ said Rick. ‘Some crime?’

‘Anything you like, anywhere in the city. To escape, to achieve game over, you need to get on board a train - any train - at the Hauptbahnhof or one of the minor stations. That’s how you hypothetically might win, while our goal is to arrest you. It’s not like you’re going to be hard to catch.’

‘But—’

‘So we’ll decamp and let you plan. Ten minutes long enough?’

Rick mouthed the word decamp.

Trudi spoke up. ‘It sure is.’

‘Then we’ll leave you to it.’

At that, Alisha, Angela and Stef disappeared. They might remain close in reality, but they would now be in some other part of the simulation, perhaps in whatever passed for Police HQ. Roger wished he’d spent more time on the city’s geography, but he’d been working on persona templates for the city’s virtual inhabitants, and two of the generics had crashed with paracognitive failures that took ages to debug.