Cooper leaned against his Toyota, noting how ill at ease the young Ranger was. Mark took a radio handset from his pocket, fingered the buttons, flexed the aerial, and put it back without seeming to realize what he was doing.

‘Tell me about it,’ said Cooper.

‘It’s Warren Leach. We see him often at Ringham Edge. He doesn’t know we’re there – he never bothers to look up at the hills these days, only down at his boots.’ Mark paused. ‘For a while now, I’ve thought there was something going on in the big shed at the back of the farmhouse. The new one, with the steel roof. It’s always locked, and Leach doesn’t go near it during the day. I’ve seen Yvonne Leach go out there and try the doors sometimes, when Warren is out of the way. She wants to know what’s in there, too.’

‘And at night?’

‘People come. Vans, four-wheel drives. They all park by the shed. But only when it’s dark.’

‘Mark, you’re not normally on patrol at night, are you?’

‘Of course not. But I’ve been up there in my own time a couple of nights. I want to know what’s going on. It’s my patch, you see. Owen told me it’s my patch now, up there.’ Mark hesitated and looked sideways at Cooper. ‘Owen doesn’t know I go up on the moor at night.’

‘All right, Mark.’

‘Leach is going through a really bad time. You’ve been to see him, haven’t you?’

‘We took a captive bolt pistol off him the other day. It was unlicensed.’

Mark frowned. ‘Why do you think Leach would have a captive bolt pistol?’

‘To use on his own animals, I suppose. There must be some he has to put down.’

‘Farmers are supposed to have their fallen stock removed by a proper slaughterman. There are regulations these days.’

‘Even so . . .’

‘Would he risk getting into trouble just for that?’

Cooper waited for him to say more, but Mark looked round at the door to see if Owen had emerged. He began to edge towards the Ranger Land Rover a few places away from Cooper’s car.

‘Have there been any people coming to the farm that you recognized, Mark?’ asked Cooper.

‘Oh, one or two vehicles that were probably local. Most of them I don’t recognize.’

‘What about a white van?’

The young Ranger nodded. ‘Ford Transit? Almost ready for the scrapyard? Front bumper held on with baling twine?’

‘Yes, that sort of van.’

‘I know him, all right. That’s the rat man.’

‘You’ve seen him down at the farm?’

‘Several times. He gets around a bit.’

Owen Fox came out of the station. He was chatting to a uniformed officer, and they paused on the steps. When Owen saw Mark, a faint shadow slipped across his face.

‘Thanks for sharing that with me, Mark,’ said Cooper.