Despite the blue paint peeling from its panels, the door was too solid for an abandoned building. It ought to be sagging from its hinges, the panels rotten or missing. There ought to be the remains of a broken lock where the door had once fitted securely to the stone lintel. But as Cooper got closer, he could see that the padlock and its hasp were not only intact, but clean and well-maintained. He crouched in front of the door, and sniffed the faint aroma of lubricating oil. Someone had been here within the last few weeks.

He turned his attention back to the door. The lock that secured it was a strong, old-fashioned padlock. Somewhere there would be a large iron key on a key-ring, safe in a drawer or sitting in someone’s pocket. But whose pocket? The Saxton Trust owned this land – but what did they know about this disused building standing among the decaying beeches of an unmanaged woodland? Who cared about the overgrown remnants of Fox House Farm?

Cooper walked around the building, careful to place his feet on the dry vegetation rather than on bare ground. He found himself surprised by the size of the place. The side wall extended well back into the trees. Yet nothing had been allowed to root in the mortar between the stones, and no saplings grew in the corners and crevices, as they always did when left unchecked. Birds dropped seeds that would germinate in the least bit of dirt. But not here. Apart from a few clumps of grass in the broken guttering, the building seemed to have resisted the encroachment of nature.

On this side, Cooper could see that all the windows had been filled in with stone and sealed. He gave one stone an experimental shove, and it didn’t budge. Maybe there was a double thickness of stone, with mortar on the inside. Or perhaps someone had used breeze block to make a proper job of it.

He moved back a few yards and looked up at the roof. Surely that couldn’t have survived in one piece? The weather would have got in and collapsed some of the timbers. But the stone tiles he could see were sound. Sound, like Tom Jarvis had been sound.

But not quite. Where the building was divided by a wall, making a sort of lean-to extension at the back, the middle section of the roof was missing, exposing the interior to the air.

Cooper approached the wall again, found a foothold on the stones and pulled himself up with the help of a branch. He teetered precariously before managing to get high enough to pull himself on to the edge of the roof with one foot where the guttering should have been. He leaned forward but couldn’t see down into the building. He shifted his weight a bit further on to the tiles to peer in.