Father Steiner gave Ben’s shoulder a gentle squeeze. Ben caught Isaac’s eye. It was foolish, he knew, but he couldn’t resist flashing a triumphant smile. The truth was, he didn’t care about the stupid boxes, nor if he packed them better than Isaac or not. But for a second there, Isaac had made Ben think he might actually have guessed what was going on. It was the mention of a game that had done it – that unconscious echo of the very phrase Callum had used. But it was as Callum had said: if they were smart, and they were careful about not being seen hanging around together too often, there was no way anyone would ever know what they were planning. If they wanted to, they could get away with murder.

Wednesday 23 October, 1.55 p.m.

Fleet had smelled death before: most recently, in the woods that bordered his home town.

This time was different. Then, he recalled, the smell had enveloped him slowly, creeping towards him like mist through the trees. Now, as he stepped on to the landing outside the door to Lance Wheeler’s flat, it was like wading through something viscous. The air was warm, stifling even, which didn’t help. The actual scent was different, too. Out in the woods, Fleet had at first mistaken the smell for decaying foliage, but here it was sharper, more acrid, like the bins at the back of a restaurant.

Fleet stepped into the flat itself. Two SOCOs were already on the scene, prowling around at the threshold of one of the rooms. The kitchen, Fleet presumed, because the flat was barely any bigger than his bedsit, and he could see the lounge ahead of him, the bathroom on his left, and the bedroom immediately to his right. The whole place, Fleet noticed, was a tip, and it could well be the state of the bathroom that was contributing to the acerbic smell. The bed – a single – was unmade; the lounge a mess of coffee mugs and pizza boxes. Even the hallway was cluttered with junk. Several battered pairs of trainers had been kicked into a corner, and there was a bicycle missing its front wheel, as well as at least a dozen used paint cans in teetering stacks. Fleet recalled Nicky saying that Lance was a painter and decorator, and in addition to the tins of paint, there was a bundle of dust sheets, and a set of overalls draped across the frame of the bike.

On the wall beside the bathroom door there was a storage heater, and Fleet could feel it kicking out heat.

‘It’s like an oven in here,’ said Nicky, beside him. She called to one of the SOCOs. ‘Any chance we could get the temperature turned down?’

‘Already asked,’ came the muffled reply. ‘Apparently it’s on a central system, and the thermostat’s broken. Nothing we can do about it from in here.’