It was an abandoned quarry. Some sites in the Peak District had been cleared up and machinery removed, then either converted to a different use, such as landfill, or restored to agriculture. This one was too recently abandoned, perhaps. The entrance gate was blocked by large chunks of calcite, left as if for display as geological samples.

Just inside the site, a series of blue shipping containers stood at one side of the roadway, with their doors left gaping open. One of them had been used as a store for equipment spares such as conveyors, pumps and screens. The sides of the interior still carried labels with faintly mysterious names: Transfer Conveyor, Crusher, Cobbles Belt, Pearls One. The door had been wedged open with a wooden pallet, and there was little left inside it now.

Outside, though, the ground was littered with long strips and rolls of black conveyor belt. They were heaped and scattered everywhere, as if the departing workers had simply thrown everything out of the containers before they left the site. Among the debris were broken bits of machinery, part of a drive shaft from a quarry vehicle. Two smaller containers were perched precariously on a pile of corrugated-iron roofing sections.

Further into the quarry was an abandoned lorry, digging equipment, a caravan that might once have been used as a site office. The signs warned of blasting and cautioned Cooper to observe a ten miles per hour speed limit. The barriers would not stop anyone who wanted to enter the site, but the machinery was too big to steal, so it had been left.

Now, only the sound of birds disturbed the site, where once there would have been a deafening cacophony of machinery, crushed stone and blasting.

‘This must have been searched at the time,’ said Cooper.

‘Oh, surely.’

He wished he could feel as confident as he was trying to sound. Something had gone wrong in the original investigation of the Pearsons’ disappearance, and he wasn’t yet sure what it was. In fact, he had no firm idea at all.

Back at the office, Luke Irvine had been landed with the job of ploughing through all the old witness statements, search reports and case files. It was a thankless task, but someone had to do it, just in case a fresh pair of eyes spotted something new.

‘I’ll get Luke to check,’ said Cooper. ‘It might make him feel a bit more involved.’

Returning to the entrance, Cooper found himself standing in a gateway looking at a little circular sign with its yellow arrow identifying the Limestone Way. He’d noticed that right below it was another sign, with no words on it, only a simple graphic. It showed a small human figure falling head first into a hole in the ground.

Its message ought to be clear. But how many people set off to walk across the moors without any realisation of the dangers under their feet?

Cooper tried to imagine the Pearsons thinking they could follow the Limestone Way in the dark, and in a snowstorm too. If that was what they’d done, it could only be called foolhardy in the extreme. He supposed they weren’t the first ill-prepared travellers to have lost their lives on these moors. But it shouldn’t happen in the twenty-first century.

12

When they arrived back at West Street, Cooper soon heard that the body at the Light House had been identified, and the dead man’s wife already interviewed. That was Diane Fry, working fast as usual. If he wasn’t careful, she’d have this whole thing tied up in a neat bow within a few days, and all his vague doubts would count for nothing.

Cooper made a point of asking Fry to bring the team up to date. He suspected it wouldn’t happen otherwise. She would be reporting to her own DCI, and local CID would get bypassed. He couldn’t bear the thought that he’d continue to be left out in the cold, wondering what was happening, until he heard about some development on the office grapevine.

Fry had been allocated an old office that had recently been vacated by some centralised civilian staff member. It was little more than a cubbyhole, with frosted glass in the windows. It meant that she couldn’t be seen when she closed the door, except as a blurred movement inside.

Rather reluctantly, she emerged from her little office and joined everyone else in the CID room. Watching her enter, Cooper could see her already in the role of a detective inspector, shutting herself off from the troops because she had more important things to do than the same old donkey work. He wondered when her promotion would come. It was long overdue now, surely? He bet Fry herself secretly thought so. It might even be eating away at her inside, making her even more grouchy than usual.

‘Aidan Merritt was never a suspect,’ Fry explained, when she had everyone’s attention. ‘He was interviewed when officers in the original inquiry were trying to trace the Pearsons’ movements over the last couple of days before their disappearance.’

‘What was his connection?’

‘The Pearsons were at the Light House the night before their visit to Castleton. So far, that seems to be the only connection with Aidan Merritt, who was a regular there. It’s a rather tenuous link, admittedly. But the fact is that Merritt’s name was in the system from the original inquiry. An officer spoke to him when they were trying to plot the Pearsons’ movements. And once you’re in the system, the computer is likely to keep coughing your name up whenever there’s a hint of a match.’

‘I went through the statements taken from Merritt and some of the other regulars,’ said Irvine. ‘It seems there was another group of visitors in the pub that night. Two men and two women. Several witnesses mentioned seeing them talking to the Pearsons. They were thought to be staying in a holiday cottage nearby too.’

Cooper looked out of the window at the distant edges of the moor. ‘Do we know which one exactly?’

‘No.’

‘The Pearsons were definitely alone at the George, weren’t they? They didn’t meet up with this other group?’

‘It doesn’t seem so.’

‘We’ll never know what was said between them, anyway. Not unless we can trace the unknown group, and that looks like a very tall order.’

‘Yes, I agree.’

For a start, they would have to identify all the holiday cottages within walking distance of the Light House. Some of them might have been sold in the last two years and converted into permanent homes. More likely, though, the trend would be the other way round. He expected to find a greater number of holiday cottages in the area now than there were when the Pearsons visited.

‘Another rented cottage, I suppose?’ he said. ‘Not one they owned themselves.’

‘Oh, I think so. If they owned it, they would probably have visited the area regularly, wouldn’t they? Someone would have known them.’

Cooper nodded. In that case, he’d be relying on a property owner with good records, or a lucky entry in a guest book.

‘Needle in a haystack come to mind?’

‘I don’t suppose it was followed up all that well,’ said Fry. ‘Another lead that was just recorded and written off, I imagine.’

This was what Cooper had been worried about. The Pearsons had been in the Light House the night before they disappeared. That had been picked up by the original inquiry, with all those unproductive witness statements taken from the likes of Aidan Merritt and the other regulars and staff at the pub.

But he was pretty sure the couple had been there the previous evening too, the night of the YFC party. Why had no one ever mentioned that?

Well, it seemed the investigation had only examined the final two days before David and Trisha Pearson went missing, at least in any detail. The SIO might have made a decision not to expend resources needlessly on trying to trace the Pearsons’ movements earlier in the week. There was a law of diminishing returns in these things. You could spend more and more time on a particular line of enquiry, allocating more and more resources, but find that you got fewer and fewer returns on the effort. Someone had to make a decision where the cut-off point came.