Already, the threat had come very close. The foot-and-mouth outbreak of 2001 hadn’t quite reached the Peak District. But there were farms a few miles south, on the border near Sudbury, where cattle and sheep had been slaughtered in the mass cull. And then along came H5N1, the strain of avian flu virus that could be carried by wild birds. Any day a poultry farmer might look up into the sky and see a flock of geese, or a skein of mallards, and wonder whether they were bringing the disease north.

Yes, there had been new enterprises at Pity Wood, but some of them were of a nature that the Suttons hadn’t understood. They had no idea that the world had changed so much around them that illegal drug manufacturing was the only way for their farm to make a profit. Ironically, it could be seen as the sort of thinking the government was trying to encourage – moving away from traditional farming to new and exciting ways of exploiting the assets of their property.

Of course, the Suttons’ big mistake had been inviting Tom Farnham in. He must have looked like a saviour at the time, promising all kinds of things, including a bright new future for Pity Wood Farm, new ways of earning income, enough money to put the farm back on its feet.

But Farnham had been the worm on the carcase of a dying animal. He’d exploited the still-warm flesh for his own short-term ends. The money had gone into his own pocket, not to the Suttons, or to safeguard the future of Pity Wood.

‘Those poor women,’ said Cooper when he heard the full story of Nadezda Halak and her coworkers from Fry. ‘They were following the instructions they’d been given, without any idea of the horrendous risks they were running.’

‘They certainly didn’t understand what the chemicals were, or how harmful their effects could be,’ said Fry. ‘And why would they suspect? They saw a collection of ordinary household products, bought over the counter, or from the supermarket shelf. Why would they think those products could be lethal?’

‘I bet they didn’t care, anyway. They just knew they were paid much better for that job than for picking carrots.’

‘You sound unusually cynical.’

‘Well, it’s another case of “Monkey See, Monkey Do”.’

‘What are you talking about, Ben?’

‘It’s a saying that refers to somebody learning a process without any understanding of how or why it works. You made me think of it before, with your thing about the Three Wise Monkeys. If something seems to work, we do it, and we don’t ask why it works. It’s the origin of most superstitious rituals, too.’

‘Oh, I think I see. The Joneses next door killed a cow last year, and they had a good harvest. So we’ll do the same.’