He was hoping there’d be time for several different test runs before the transplant, but with Zendegi’s health looking as precarious as his own, he needed to be prepared to make a judgement as quickly as possible. So if he wanted to see the Proxy jump through hoops, there was no point starting with any but the highest, and no point sparing the flames.

Nasim collected Martin from the hospital and drove him across the city. She seemed nervous, but it was clear from her demeanour that the optimistic verdict she’d given him after her own tests had been genuine. The Proxy had not disappointed her; the only thing she feared was that Martin might not feel the same way.

It was half past seven when they arrived, but despite the chilly morning Shahidi’s supporters were out in force. Martin had only been following the politics sporadically, but he’d heard Zendegi’s side-loads being lumped together with a whole grab-bag of permissive and un-Islamic trends. The respectable conservative line went like this: Nobody wanted the corrupt mullahs back, lining their pockets and throwing their enemies into prison, but the pendulum had swung too far and a correction was desperately needed. A vote to rein in immodesty and blasphemy would be the antidote to extremism, dealing with popular discontent before it exploded into a violent backlash.

In the MRI room, Nasim fitted Martin’s skullcap. Bernard was having a day off; his trainee, Peyman, was operating the scanner. There was no need for contrast agents; they would not be collecting side-loading data today. The only reason Martin was here and not in a ghal’e was that controlling his icon mentally, via the scanner, would spare him from fatigue and allow him to fake a few futuristic tweaks to the system.

Nasim said, ‘Don’t get alarmed if the Proxy doesn’t show up for a few minutes; it’s hard to say in advance how long I’ll be talking to it.’

‘Okay.’

‘Feel free to kill the game any time you want to, or to keep running it for as long as you like. The scanner’s yours for three hours if you need it.’

‘Thank you.’

Nasim flipped down his goggles and fitted the cage over his head. Martin waited for the whirr of the motor that would carry him back into Zendegi.

The dying embers of a campfire lay in front of him; an orange light was breaking on the horizon. Martin stretched his arms out, feeling his way into his new body; the hands and forearms that came into view belonged to a giant, but the skin was as smooth and unlined as a child’s. Zal’s son Rostam had been preternaturally huge; only the Simorgh’s intervention – in which the bird had offered detailed advice on the herbal drugs to use for a Caesarean – had allowed Rudabeh to give birth to him and live. But Rostam’s son Sohrab was even more prodigious; the Shahnameh had him playing polo at three, shooting arrows and throwing javelins at five, and leading a conquering army at the age of ten.

Martin turned away from the dying fire. He was standing on a slight rise; below him, embroidered tents and horses draped in silk brocade carpeted the desert as far as he could see. Around the tents, soldiers were finishing their meals, completing their ablutions and tending to their mounts. He could remember when a crowd scene like this would have needed a Hollywood budget and an hour’s worth of computations to render each frame; now it was being done in real time for his eyes alone. Or his, and one other pair.

As he surveyed the camp, the soldiers who glanced his way quickly lowered their gaze in deference to their ten-year-old general. He had asked Nasim to modify the way he saw the Proxy, retaining some resemblance to his own appearance but changing a few parameters to break the spell; it would be hard enough playing his own peculiar role without the distraction of a mirror-image of his true self standing in front of him. The preview she’d emailed him had seemed workable – and it had looked so much like one of his uncles that Martin had decided to call it privately by the same name. His Uncle Jack had died twelve years before, and Martin had not been close to him since childhood, but borrowing his identity felt less strange than picking a name at random.

When the white-haired man clad in armour strode towards him up the rise, Martin started to have second thoughts about his choice, but it was too late for that. Javeed would see the same icon as he’d seen from their very first trip together, so Martin did his best to let the sense of familiarity overwhelm everything else.

‘Javeed?’ Jack broke into a grin of delight and disbelief. ‘I thought you might outgrow me one day, but this is ridiculous!’

‘Welcome back, Baba.’ Martin stepped forward and reached down to take his hand.

Jack was speechless for a moment, overcome with emotion. Martin tried to appear affectionate, but also a little blasé; the experience was meant to be anything but new to him. For Jack, every time would feel like the first time he was seeing his son again after his death. But Martin understood why Nasim had insisted that it be this way; not only had the side-loading process been pushed to its limits to get this far, she hadn’t wanted to curse the Proxy with a sense of its own life in time.

Martin drew his hand away. ‘Does it help if I tell you that it always helps when I tell you that you always get over the shock?’

Jack burst out laughing. ‘Absolutely!’ He looked away, fighting back tears. ‘Ah, pesaram. I wish-’ Martin knew how the thought ended: I wish your mother could have seen you like this. But Jack passed the test and kept silent; Javeed didn’t need that wound torn open, week after week.

‘What’s happening at home?’ Jack asked him. ‘How are Uncle Omar and Aunty Rana?’

‘They’re good,’ Martin said. ‘The shop’s still going well. Umm… Uncle Omar’s father died last year.’

‘I’m sorry. What happened?’

‘He had a heart attack.’ Martin underplayed it, as if to say: It was sad, and I’ll miss him, but he was a very old man, trying to appear neither anguished nor untouched.

Jack seemed to be on the verge of pressing him for more, but then he caught himself; whatever need there’d been to discuss the death, that conversation would have happened long ago. ‘How’s Farshid?’

‘He got married. He’s got a daughter now.’

‘That’s great. Are they living with you and Omar?’

‘Yes.’ Martin hesitated. ‘I don’t think his wife likes me very much.’

Jack said, ‘Maybe she’s just a bit jealous, because you and Farshid are so close.’

Martin didn’t reply and Jack let it drop. ‘What about school?’ he asked.

‘School’s okay. I’m getting good marks in Farsi and English. And I’m the third fastest runner in my grade.’

‘Mubaarak!’

Martin spread his bulky arms. ‘But today I think I’d make a good wrestler.’

Jack laughed. ‘So you’re Sohrab?’

‘Yeah. Do you remember the story? Rostam was hunting along the border with Turan, and one night his horse went missing. While he was looking for Rakhsh he hooked up with Princess Tahmineh, but all he really cared about was his horse; he didn’t hang around to look after the kid.’

Jack smiled uneasily; perhaps he knew that this tale of parental neglect turned out rather less happily than that of Sam and Zal.

Martin said, ‘Don’t worry, Baba, you’re not playing Rostam. I made up a new character, an adviser from Princess Tahmineh’s court who travels with her son as a kind of guardian.’

‘A kind of guardian,’ Jack echoed. Maybe the demotion stung a little, but it was better than the fate in store down the line for Sohrab’s father.

A bearded Turani nobleman approached Martin and bowed low. ‘My lord, the sun is risen and your soldiers await your instructions.’ Martin wanted to laugh – just as he and Javeed had once giggled at Kavus and his sycophants – but he stayed in character: twelve-year-old Javeed playing the revered boy-general Sohrab.