Cooper watched Farnham working on the lawnmower for a moment. Strong, capable hands slotted a rotor blade back into place.

‘Can you think who the victim might be, Mr Farnham?’

‘Victim?’

‘The body we found at Pity Wood. The body of a woman.’

‘No, I can’t.’

‘Please think carefully. Anything you can remember might help us with an identification. A woman who disappeared around twelve months ago?’

Farnham didn’t even look up from his task. ‘No, sorry.’

‘I understand there were a number of itinerant workers employed at Pity Wood Farm. Would that be during your time, sir?’

This was a fact that could be checked, so a lie would soon be caught. Cooper saw Farnham working that out for himself before answering. He took a little too long fitting parts of the motor back together.

‘Yes, it would. Like I said, we tried out quite a few diversification schemes. Horticulture, poultry … Some of them needed labour at certain times of the year. Often casual labour. So, yes – we had itinerant workers, if you want to call them that.’

‘Well, we’ll need records. Details of the workers employed at Pity Wood during the last couple of years. You were a sort of farm manager, so …?’

‘Ah, well. Records.’ Farnham straightened up, wiping his hands on a rag. ‘Those will be at the farm, such as they are. I left the farm accounts with Raymond. They weren’t the best at record keeping, you know. They didn’t believe all the bureaucracy and paperwork was necessary. But anything there is, you’ll find it at Pity Wood.’

‘Thank you, sir.’

‘Oh, if the builders haven’t thrown them out already,’ said Farnham, as if the possibility had just occurred to him. But his air of innocence wasn’t convincing Cooper.

It was cold in the workshop. And where it wasn’t wet, it was oily. Farnham had a battered white Subaru pick-up with mud-caked hub caps, but it stood outside on the drive to provide more room in the garage.

‘Do you spend much time out here?’ asked Cooper.

‘As much time as I like,’ said Farnham. ‘I’m a widower, you see.’

As he drove away from Farnham’s house, Cooper looked afresh at the landscape. An ideal reservoir site should have a ring of hills to reduce the amount of dam building required. Rakedale had that. It also had the necessary clay soil, which stopped the water seeping through and provided material for dam construction. That was why the limestone areas had avoided reservoir building. Much too porous, limestone. If they’d built the reservoirs a few miles further north, Manchester would be suffering a permanent drought.