‘Case!’ Coach barked. ‘Ever thought about cross-country?’

Boy’s ears flicked forward. He liked a good run.

Justin looked behind him.

‘You, Case! Did you hear what I said?’

Justin nodded.

‘Well? We need more runners this year.’

‘But I can’t run.’

‘Bollocks,’ Coach spat. ‘Look at you. With a little training you could run all day.’

Justin stared at Coach, amazed and suspicious. David Case had never looked like a runner. It was one thing to change your shirts, quite another to assume an entirely different body type.

‘Case!’ Coach snapped impatiently. ‘You’re not brain-dead, are you? That could disqualify you.’

Justin shook his head: But I hate sport. And then: Perfect.

Coach rolled his eyes. ‘An answer, Case. Any answer will do.’

‘OK,’ said Justin. Boy wagged his tail.

Peter grinned when he heard. ‘You’ll like it,’ he said. ‘Not at first, of course, it’s horrible at first. But you get used to it eventually.’

Justin didn’t expect to like it, now or ever. Cross-country seemed a perverse sort of self-abuse consisting of endless gruelling runs through the unattractive suburban landscape egged on by a wisecracking sadist whose life had repeatedly been blighted by mediocrity.

Coach’s team had never captured a county championship. Coach himself had never discovered a future Olympic champion. No boy had ever returned to Luton Secondary years later to report that running had played a formative, nay, pivotal role in his life. The extra pay Coach received for three afternoons a week enduring the contempt and indifference of fifteen talentless teenage boys did not begin to compensate for the extent of his disenchantment.

Despite knowing all this, Justin was secretly pleased to have been plucked from athletic obscurity. No one had ever suggested that he could run at all, much less all day. David Case was certainly no athlete, but Justin? Justin was loaded with potential.

Without his noticing, he had already begun to change shape. Over the previous eighteen months he had grown six inches. His legs, always disproportionately long in relation to his torso, had lengthened further and his feet had grown two and a half sizes. But he was soft and slow, and it took a leap of faith to imagine he’d ever be different.

His first practice involved circling the school track at what felt like excessive speed, with Boy bounding around him joyously. After ten minutes he began to flag. Thirty minutes left him collapsed by the side of the track gasping for air, legs shaking and contracted with cramp, lungs on fire, throat dry, stomach heaving. Boy licked his face once, then settled down gracefully next to him for a nap.

‘Hey, you suck!’ hissed one of his teammates.

One by one they passed, skimming around the grey outdoor track, each competing for the most hilariously entertaining insult.

‘Hey, Granny.’

‘Puss puss pussy.’

‘Dickhead.’

‘Oi! Head Case!’

This last, from Coach.

Justin barely noticed the insults. He was too busy trying to restore the flow of oxygen to his brain.

Peter said nothing as he flew past, but his silence exuded compassion.

Seven of the fifteen boys on Justin’s team had been chosen for their ability to outrun the local constabulary, five others were blackmailed into participating, their academic potential so limited that alternative excuses had to be found to keep them in school. Most of this group whiled away unsupervised moments stopping for fags by the side of the track.

Justin didn’t smoke, so he ran instead, discovering in the process that Coach’s evaluation had not been entirely wrong. Day by day he improved, modestly, steadily; soon he discovered a jawline and hard planes of muscle in his legs. He began to look different, rangy and fast, and best of all found he could run more or less indefinitely. His chest would eventually feel crushed under the strain of oxygen deprivation, at some point his muscles still pleaded with him to stop, but the pain took longer to set in, bothered him less, became familiar. He could keep up for longer periods and when he matched Peter stride for stride he felt triumphant.

His dog helped, loping gracefully by his side, lean and effortless. When Justin felt discouraged he concentrated on Boy’s stylish gait, his noble spirit.

I am a greyhound, Justin thought as he ran, I am king of dogs. I skim through time and space at the speed of thought. The unknown is my prey, I bring it to earth in a single exquisite bound.

He could feel the syncopation of his paws on the track, his narrow muzzle piercing the air, no sound except the pounding of his large, noble heart. He ran silently. He was an air hound, a sight hound, deadly in pursuit of a rabbit, a taut bow, a spinning arrow. For whole minutes at a time he was graceful, joyous.

The insults tailed off, at least from Coach.

‘How’d I do?’ Justin asked, panting, his legs shaking, body streaming with sweat.

‘Jesus,’ Coach muttered, staring at his stopwatch. Ten thousand metres in just under thirty-eight minutes.

Justin’s chest swelled with pride. A few weeks ago he could barely stagger round the track.

It gave him hope.

Perhaps whatever it was, he could outrun it.