‘Yes, Diane. I think they’ll find a voice changer somewhere among all that stuff they’ve taken out of the house. Or maybe in Vernon’s car.’

‘How can you be sure?’

‘He was at the councillor’s funeral in Wardlow, you know. That was a Hudson and Slack job, and Vernon was one of the drivers. It might have looked odd for one of the mourners not to go into the service, and someone might have noticed that. But the drivers wait outside the church. Vernon was ideally placed to make that call.’

‘What about the call from the crematorium, though? That funeral was being conducted by a firm from Chesterfield. It wasn’t Hudson and Slack’s job.’

‘But the one before it was theirs, Diane. There was a half-hour turnaround at the crematorium. The limousine drivers from the previous funeral were just waiting for the mourners to finish inspecting the floral tributes. They were away out of the gates long before we arrived.’

Fry had been looking at the pellet marks too long now. She couldn’t even have been seeing them any more.

‘And Vernon was there?’ she said.

‘I’m sure he must have been driving one of the limos that day.’

She looked at Cooper then with an eager expression, as if there was something she needed from him.

‘Ben, he said there was going to be a killing. What killing did he mean?’

Cooper frowned. ‘I don’t know. There’s only one person’s death you can fully control, isn’t there? There’s just one form of dying that has an unambiguous meaning. That’s when you take your own life.’

‘You think that’s what he planned to do?’

‘People don’t get to choose how they die. With one exception: suicide. It’s the only way we can have any control over our own death. The only way we can give the end of our lives any meaning.’

Cooper knew that suicide was often an act of anger against people who were close to the victim but had failed to recognize their despair. Or it could be aimed at those who caused the despair in the first place. In its way, suicide was an especially cruel form of revenge.

But Fry looked unconvinced. He guessed she might be remembering the words of one of the phone messages: As a neck slithers in my fingers like a sweat-soaked snake … They would never know whether Vernon had been referring to a real killing or re-living a fantasy. Was that what he’d been thinking as he sat in the wrecked van with his father helpless at the wheel? It was a moment when he might have acted out his fantasy of killing the man he hated.

‘You know Vernon Slack studied under Professor Robertson?’ said Fry. ‘He was the professor’s star student, apparently.’

‘So he’s not quite as dumb as he seems.’