They waited.

‘So now Andie’s dead.’ Pip pointed down at the gravel road. ‘He opens the boot –’ Pip opened her boot – ‘and he picks her up.’ She bent down and held out her arms, taking enough time to lift the invisible body. ‘He puts her inside the boot where her blood was found.’ Pip laid her arms down on the carpeted boot floor and stepped back to shut it.

‘Now back in the car,’ Ravi said.

Pip checked the timer: 20:02, 20:03 . . . She put the car in reverse and swung back out on to the main road.

‘Sal’s driving now,’ she said. ‘His fingerprints get on the steering wheel and around the dashboard. He’d be thinking of how to dispose of her body. The closest possible forest-y area is Lodge Wood. So, maybe he’d come off Wyvil Road here,’ she said, turning, the woods appearing on their left.

‘But he would have needed to find a place to get the car up close to the woods,’ said Ravi.

They chased the woods for several minutes searching for such a place, until the road grew dark under a tunnel of trees pressing in on either side.

‘There.’ They spotted one together. Pip indicated and pulled off on to the grassy verge that bordered the forest.

‘I’m sure the police searched here a hundred times, as these are the closest woods to Max’s house,’ she said. ‘But let’s just say Sal managed to hide the body here.’

Pip and Ravi got out of the car once more.

26:18.

‘So he opens the boot and drags her out.’ Pip recreated the action, noticing the muscles in Ravi’s jaw clench and release. He’d probably had nightmares about this very scene, his kind older brother dragging a dead and bloodied body through the trees. But maybe, after today, he’d never have to picture it again.

‘Sal would have had to take her quite far in, away from the road,’ she said.

Pip mimicked dragging the body, her back bent, staggering slowly backwards.

‘Up here’s pretty hidden from the road,’ Ravi said once Pip had dragged her about 200 feet through the trees.

‘Yep.’ She let go of Andie.

29:48.

‘OK,’ she said, ‘so the hole has always been a problem, how he could have had enough time to dig one deep enough anyway. But, now that we’re here,’ she glanced around the sun-dappled trees, ‘there are quite a few downed trees in these woods. Maybe he didn’t need to dig much at all. Maybe he found a shallow ditch ready made for him. Like there.’ She pointed to a large mossy dip in the ground, a tangle of old dry roots creeping through it, still attached to a long-fallen tree.

‘He would’ve needed to make it deeper,’ Ravi said. ‘She’s never been found. Let’s allow three or four minutes for digging.’

‘Agreed.’

When the time came she dragged Andie’s body into the hole. ‘Then he would have needed to fill it again, cover her with dirt and debris.’

‘Let’s do it then,’ Ravi said, his face determined now. He stabbed the toe of his boot into the dirt and kicked a spray of soil into the hole.

Pip followed suit, pushing mud, leaves and twigs in to fill the small ditch. Ravi was on his knees, sweeping whole armfuls of earth over and on top of Andie.

‘OK,’ Pip said when they were done, eyes on the once-hole that was now invisible on the forest floor. ‘So now her body is buried, Sal would have headed back.’

37:59.

They jogged back to Pip’s car and climbed inside, kicking mud all over the floor. Pip three-point turned, swearing when a horn screamed at them from an impatient four-by-four trying to pass, her ears ringing with it all the way.

When they were back on Wyvil Road she said, ‘Right, now Sal drives to Romer Close, where Howie Bowers happens to live. And he ditches Andie’s car.’

They pulled into it a few minutes later and Pip parked out of sight of Howie’s bungalow. She blipped the car behind them.

‘And now we walk to my house,’ Ravi said, trying to keep up with Pip, her steps breaking into an almost-run. They were both concentrating too hard for words, their eyes down on their pounding feet, treading in allegedly Sal ’s years-old footsteps.

They arrived outside the Singhs’ house breathless and warm. A sheen of sweat was tickling Pip’s upper lip. She wiped it on her sleeve and pulled out her phone.

She pressed the stop button on the timer. The numbers rushed through her, dropping all the way to her stomach, where they began to flutter. She looked up at Ravi.

‘What?’ His eyes were wide and searching.

‘So,’ Pip said, ‘we gave Sal an upper-limit forty-five-minute time window between locations. And our re-enactment worked with the closest possible locations and in an almost inconceivably prompt manner.’

‘Yes, it was the speediest of murders. And?’

Pip held her phone out to him and showed him the timer.

‘Fifty-eight minutes, nineteen seconds,’ Ravi read aloud.

‘Ravi.’ His name fizzed on her lips and she broke into a smile. ‘Sal couldn’t possibly have done it. He’s innocent; the photo proves it.’

‘Shit.’ He stepped back and covered his mouth, shaking his head. ‘He didn’t do it. Sal’s innocent.’

He made a sound then, one that grew slowly in his throat, gravelly and strange. It burst out of him, a quick bark of laughter shaded with the breathiness of disbelief. The smile stretched so slowly across his face, it was as though it were unfolding muscle by muscle. He laughed again, the sound pure and warm, Pip’s cheeks flushing with the heat of it.