‘In side-loading, you get to peer inside the box, even if you don’t get to take it apart. You don’t have the resolution you’d get by peeling the brain with an ATLUM, but you have the advantage that you can expose the living brain to all kinds of stimuli – words, images, sounds, tastes, smells – and see how they bounce around inside the skull. And it doesn’t really matter how little external behaviour is evoked if you can watch the pattern of internal changes rippling out from every stone you toss in.’

Nasim said, ‘That all sounds fine in principle. But how far has it actually taken you?’

Caplan gestured at the Eikonometrics report. ‘Six months ago, we took a rat that had been trained to solve a particular maze. By observing its brain’s responses to a barrage of random sensory cues, we managed to modify an initially unrelated virtual rat to run the same maze.’

‘Observing its brain how? Do you mean micro-electrodes snuggling up to ten thousand neurons?’

Caplan shook his head. ‘Not at all. Purely non-invasive methods: multi-mode MRI and surface electrodes.’

Nasim was impressed now; this was more than she’d expected. ‘And with humans?’

‘With humans,’ Caplan said, ‘the problem is that we don’t really have a good generic virtual brain to use as a starting point. When the HCP published their results we started trying to construct one, but it looks as if you’re doing a much better job at that than we are so far.’

Nasim mulled over this frank assessment, sting included. The algorithm she’d used on the finch brains was public knowledge, but it wasn’t so cut and dried that someone coming in cold could apply it to the HCP scans and expect to crank out a good result. So she had a head-start on the path towards something Caplan wanted, badly – but it would be a mistake to overplay her hand and imagine that this made her indispensable.

‘So you think Eikonometrics can find a way to side-load languages into my Proxy modules?’ she asked.

‘I think it’s worth trying,’ Caplan said. ‘I think it’s your best chance. And there might be some other useful skills you could endow them with, the same way.’ He smiled. ‘Since I got your email, I’ve been giving that some thought. Suppose you could side-load motor skills from a few celebrity athletes: sign up the right soccer players and the Middle East is yours again. Add the right cricket players and Cyber-Jahan is history.’

Nasim was speechless. Motor skills were probably the simplest case imaginable – certainly less challenging than side-loading a second language. And Caplan was right: millions of people would vote with their credit cards to ‘play beside’ their sporting heroes, captured with an authenticity that no celebrity-endorsed console game could ever come close to achieving.

The most she’d been expecting from Caplan was a modest cash injection, giving her a chance to pursue her research far enough to see if it could be commercialised. Instead, he’d just offered Zendegi a plausible route to market domination.

Nasim forced herself to reply coolly, ‘It seems we both have something the other could use.’

Caplan inclined his head in agreement.

She said, ‘I’m going to have to discuss this with my superiors.’ If the Eikonometrics research was as promising as Caplan made it sound, Nasim was sure she could hook them on the sporting angle alone. ‘And there’ll be a complex joint venture agreement to be thrashed out-’

Caplan said, ‘I understand. Bring on the lawyers! But don’t run away and hide this time. Don’t forget, you’re at the heart of the deal.’

Nasim laughed, but she regarded his bland, youthful icon with unease. Caplan would emerge with a substantial stake in the company, but this wasn’t just about the cash flow that a synergistic marriage of their technologies could yield.

By setting up this meeting, she’d probably saved her job, her employer, her career… but no amount of commercial success with the Proxies would be enough for Caplan. She knew what the only worthwhile endpoint was for him – and she’d just agreed to harness herself to his cause.

Martin ran two kilometres on the treadmill. It took him fifteen minutes, and by the time he’d finished he was drenched in sweat – but then, that was the whole point of the exercise.

He grabbed a mat from a pile in the corner of the gym, put his towel over it and knelt down. He wiped the sweat from his eyes, then slipped on the goggles that were linked to the Physiotherapy Department’s computers. When he looked down, his clothes had vanished from sight, along with much of his body: skin, fat, blood vessels, genitals, viscera. All that remained of him was muscle, bones and tendons. The towel beneath him was gone as well; he appeared to be kneeling on a transparent cushion that was supporting him over a mirrored surface that had replaced part of the gym’s carpeted floor.

He moved his right foot in front of him, to the left, as he lowered his chest towards the ground, stretching out his left leg behind him to lie flat, while his right leg was bent and trapped beneath him. Looking down at his virtual reflection, he could see the piriformis muscle that crossed his right buttock at the back of his hip, helpfully highlighted in blue.

The operation to remove the tumour on his spine had impinged on a nerve in his spinal cord, giving rise to a month of excruciating pain. The pain felt as if it was in the muscle, though that had not actually been damaged at all: the pain there was a phantom, a false message. But his body didn’t know the difference, and the muscle had clenched up tightly to protect itself against the perceived injury. Now that the nerve had settled down, that tightness had turned the original phantom pain into a self-fulfilling prophecy: the piriformis muscle really was the problem now. Not only had it been damaged by its own defensive response, by refusing to move normally it was pulling everything else around it out of shape. It needed to be coaxed back into its old routine, but after a month spent cowed and quivering, that was easier said than done.

Martin leant forward as far as he could; the pressure on his right leg as he folded it against his body was transferred to the piriformis, stretching it a little. He kept the position for a count of twenty, then eased off.

Resting, he gazed down at the reflection of the back of his leg, at the inelegant network of fleshy ropes that had managed to tug itself so far out of balance that he was still taking painkillers just to sleep. There was something almost comical about the fact that the cancer itself had, so far, given him no pain, and the sophisticated drugs targeted against it had left him with none of the side-effects he’d been prepared to face, based on a lifetime of media images of people on chemotherapy. Instead, he just felt as if he’d been kicked in the arse by a donkey.

He leant forward again, holding the stretch to thirty this time, trying to persuade the stupid muscle that its cringing was only making things worse. When he relaxed he scrutinised the result; he could have sworn that the bundle of blue fibres was already a few millimetres longer than when he’d started. But the imagery he was seeing wasn’t likely to be that accurate; he didn’t have magic MRIVISION, showing him his true anatomy in real time. It was all just an educated guess, a simulation cobbled together from a month-old scan and some postural cues extracted from ceiling cameras in the gym and the goggles’ superficial teraHertz view of his body. It could help him perform the exercise correctly, by looking for the same information as a human physiotherapist would, but that was it. He couldn’t look down and search himself for new secondary tumours.

He did the piriformis stretch five times, then swapped legs and repeated the set; his left side was giving him no trouble, but the aim was to keep everything symmetrical. Then he went through half-a-dozen other lower-back exercises diligently enough, but with rather less zeal. They were all beneficial, and he didn’t doubt his physio’s advice for a moment, but it was hard to feel a sense of urgency over slightly stiff hamstrings; none of this routine was going to make a difference to the cancer, at least not directly, but if he could win back pain-free days and drug-free sleep, that would be both a victory in itself and a plausible boon to his overall health.