‘Sorry?’ Elder cocked his head as if he had misheard and thought his ear might have suddenly become blocked. ‘Did you say “dogging”? Are you talking about people walking their dogs? But they do that everywhere.’

‘Walking their dogs? Hardly.’

Elder looked even more puzzled.

‘It’s one of those modern expressions, I suppose,’ he said. ‘Something to do with the internet? Or mountain bikes. Or those skateboarding things. They have their own languages, the young people. I can’t understand a word they’re saying sometimes.’

‘The fact is, Mr Elder, couples park up in some of these out-of-the-way places at night for the purpose of having sex in their cars.’

‘Oh, is that all?’ said Elder.

‘Not quite. Sometimes there are people there who watch them doing it.’

‘Those are peeping toms,’ said Elder. ‘Voyeurs, you might call them. Well, that’s not new. We’ve always had them. We had sex in my day, too, you know – just not so much of it, and more discreet. In those days, peeping toms had a hard job of it, so to speak.’

Elder smiled. Fry felt that familiar frustration of trying to get through to people who seemed to talk a different language from her own. Most of all, she hated those secret little smiles and nods of understanding that sometimes passed between Ben Cooper and people like this Elder. It was as if the fact they were born within a few miles of each other gave them some hidden means of communication that no one else could ever learn. She was glad she’d let Cooper go.

‘You don’t understand, Mr Elder,’ she said. ‘This is watching by arrangement. It’s part of the thrill, apparently.’

Elder’s eyes popped. ‘They want folk watching them while they’re doing it?’ He considered the prospect, didn’t find it appealing, and shook his head. ‘No, I can’t see it. I’d call it perverted. But I suppose things are different now. Is that really what they get up to at night?’

‘And not just at night either. Lunchtimes, even. During their breaks from work. Sometimes it’s at a date and time fixed up in advance. Sometimes they just go along to a well-known dogging spot like Godfrey’s Rough and see what turns up. The people who do the watching are the ones called doggers.’

Elder was quiet, trying to imagine the scene in the woods.

‘I suppose this is shocking you, Mr Elder?’

‘It’s a new idea, that’s all. And it’s a bit too late for me to learn, maybe?’

‘I think not, sir.’

‘Happen they’re not doing any harm, anyway,’ said Elder. ‘Have you thought of that?’

‘The point is,’ said Fry, ‘things can sometimes go wrong. Doggers have been known to fall out with each other. People try to join in when they’re not wanted … Well, you can imagine. It’s fraught with dangers.’