Cooper felt a sudden stab of guilt. It was quite irrational, and something he could never admit to Fry. But, sitting here in this tragic house, almost surrounded by human corpses, he felt guilty that he’d never found out who shot Tom Jarvis’s dog. Now, poor old Graceless would be pushed so far down the list of priorities that her death would lie on the files for ever, and her killer would never face justice. Mr Jarvis would become just one more person Cooper hoped never to meet on the streets of Edendale, in case he was challenged for an explanation.

He looked at Fry. There was something else that needed explaining.

‘Diane, there’s something about the tapes of those phone calls, isn’t there?’ he said. ‘A personal reason you find them so hard to listen to?’

‘How did you know?’

Cooper almost told her, but held his tongue at the last second. Some instinct suggested it wouldn’t be wise to tell the truth for once.

‘I just guessed.’

But Fry had that look on her face again, the one that suggested she didn’t believe him. ‘Don’t worry, Ben. I think I know who must have told you.’

‘No, really –’

‘Well, maybe you’re right,’ she said. ‘But it doesn’t matter.’

Fry watched the scenes of crime team carrying out the last boxes to one of the vans. There was still a lot of activity around the nearest tent, where Freddy Robertson’s body hadn’t been removed to the mortuary yet.

‘But Robertson could still have told us what he knew,’ she said. ‘He could have saved his own life, he could have saved Vernon’s. What was wrong with the bloody man?’

‘Do you want my expert opinion?’ said Cooper.

‘Go on, then.’

‘He was just weird.’

Fry caught the look in his eye and saw the joke.

‘Oh, that’s your view as an expert? You haven’t just borrowed that opinion from someone else and used it as your own, I suppose?’

‘I’m very experienced in my field,’ said Cooper.

‘Yes, as long as it’s a field of sheep.’

Cooper struggled to keep pace with her as she walked out of the house and headed towards the lane, past the crime scene vans. ‘By the way, Diane, what sort of fees can expert consultants claim? Do I send my invoice to you, or to the DI?’

And then Fry laughed. It was the first time he’d seen her laugh for months. It altered her whole face, the way the sun could change the landscape after rain. She looked at him and opened her mouth to speak, and Cooper felt his heart lift, as if she were about to tell him something he’d waited years to hear.