My eyes adjusted to the gloom. Out of everything I thought could be in the truck that might speak to both Michael’s innocence and his whereabouts last night, this hadn’t even crossed my mind. I stood stunned for a few seconds, until there was a bash on the flank of the truck. Sofia called, muffled but distinct: ‘Well, what is it?’

I walked to the entrance and slid the door down, sealing myself in the dark. Erin had been right. This was for me, and me alone.

The coffin still had rivers of dirt caked into the joinery. That explained the smell of fresh earth. I examined it with the glow of my phone’s torch (battery: 37%). The coffin looked expensive, made of robust wood, perhaps oak, which was well varnished enough not to have degraded too badly, and it had ornate chrome handles on either side. It didn’t look new, but it didn’t look a hundred years old either. It was hard to tell. Lucy would be pleased: as far as alibis for consummation go, graverobbing was a pretty good one.

My first thought was that this could be Holton’s coffin, purely because I couldn’t figure out who else my brother would have cause to dig up, and it had a nice circular irony that he was the man my brother had tried to bury in the first place. But this was a coffin designed for showing off, for open caskets, for someone loved and respected. Given Michael had told me Alan owed money to half the prison population, I didn’t think anyone would have reached into their pockets to give Holton such a resplendent resting place.

I dragged my fingertips lightly over the wood as I walked the length of it. The truck’s axle creaked as I shifted my weight across the thin metal floor. I saw that a row of nails had been pulled up around the rim of the casket so the lid could open. I realised that this might not be a coffin at all, but a storage box masquerading as one, and perhaps Michael had already taken what he wanted from it. People hide things in coffins, right? But if that were the case and he’d emptied it, why did he need me to see it? And if it was a person, how was I supposed to identify someone who had been in the ground so long? A pile of bones would mean nothing to me, unrecognisable no matter whose they were. As I was thinking all of this, my fingertips brushed against a rough groove on the otherwise polished wood. A marking. I shone my torch (battery: 36%) over it.

An infinity symbol, carved into the wood.