The water had never dropped as low as it did that summer, not since the reservoir was built and filled more than a century before. Even the record-breaking drought of 1976 hadn’t drained it quite to that extent, though it was close, according to Amy, who’d checked the Met Office data. When the police returned to search the lake for the body that no one but Harper was convinced was under there, they could still see the tip of the old church sticking up above the surface. It was only the second time it had been seen since the water covered it up in 1896, its weathervane, amazingly, still standing almost straight on a sliver of rusty metal. Of all the buildings that survived in the lake, it was the last thing to disappear, the first thing to be revealed.

Harper led the search, and it wasn’t long before they pulled the human skull from the water and laid it carefully on black plastic sheeting. She looked at the skull for a long time before she turned and addressed her team of divers in a hushed voice.

“This is a crime scene, people. Let’s give it everything we can.”

On the first day, they surveyed the vast search area, using a diving camera to photograph everything that lay under the surface of the reservoir, where the drowned village of Selverton once thrived. The images showed mostly piles of rubble, but also several buildings that were untouched, preserved, with furniture floating around as if in a broken snow globe.

Thrupp put the brakes on the investigation when he learned how extensive the search would have to be.

“It’s a historic case,” he said. “We can’t afford to direct resources to it, not when there’s so much else happening right now that we need to cover.”

Harper remained calm, though she wanted to scream with frustration. “This is a new murder investigation, historic or not,” she said. “We should prioritise it for that reason.”

“Do you have evidence to prove it was murder, not an accident?”

Harper had to admit that she did not. The body was unidentified, and didn’t immediately appear to relate to any missing-persons case they could find in any police archive. Damage to the bones would need to be assessed by a specialist, to determine whether injuries occurred before or after death. Harper felt that she didn’t need to wait to read the forensic pathologist’s report. She just knew it was a bad death, preventable, and unjust. The bones themselves seemed angry to her.

“You’ve got a week,” he said, “and that’s it. Unless we find something to identify the body, or something that points to foul play.”