‘Most likely. I’ve never asked them any questions. I’m not daft enough for that.’

‘Has the new fence kept them out?’

Jarvis snorted again. ‘You don’t keep poachers out so easily, not these days. They’re professionals. They work in teams, and they come kitted up. No gamekeeper would tackle a poacher on his own these days. He’d likely get his head beaten in.’

‘Yes, I know.’

The presence of poaching gangs might explain everything. They’d most likely be from out of the area, so no one would recognize them. They’d be armed, and not happy about someone else’s overly boisterous dog interfering with their business. If the estate had noticed poaching going on, it would explain the new fence, too. But what game was available in these woods that would be worth poaching? No more than a few rabbits, surely?

Cooper looked around. Down here, the moss was so thick on the wall that it looked as though someone had knitted a bright green sweater for it, draping it in folds of Arran wool. A hollow in the rocks above the track was completely covered in moss and hung with ferns, like a waterfall without the water – except for the continual dampness seeping through the surface. He wondered if some of these fungi were the kind that excreted acids to dissolve rocks and reduce them to soil. Everything decomposed, in the end.

They began to climb back towards the house. Seen from below, the heavy porch seemed to have pulled the house into an awkward shape. It looked hunched and low, like an animal waiting to spring. Cooper remembered the other thing he’d come here to ask Tom Jarvis.

‘Mr Jarvis, you have several dogs on the premises,’ he said.

Jarvis looked at the dogs, then back at Cooper. Why did he need to waste words? Cooper had already wasted an entire sentence.

‘I’ve just been watching a special support dog in action.’

Jarvis tugged off one of his gloves with his teeth, then removed the other and put them both into his pocket, like someone preparing for action, or a man who was finding the conversation boring. Cooper felt he was about to lose his attention altogether.

‘The thing I’m wondering, sir,’ he said, ‘is why none of your dogs detected the smell of a decomposing body that lay on the edge of your property for months.’

‘I don’t know. You’d better ask them.’

‘Most dogs would detect something like that. The odour is very strong for a while. In some stages of decomposition, it’s quite unmistakable.’

‘I don’t let them go into those woods,’ said Jarvis impatiently. ‘I told you, they never go in there. Well, except for the old lass, and look what happened to her.’

‘Even so …’

‘Look, I don’t know. Maybe the smell of cack threw them off the scent.’