“Aye, that should do us,” said Barclay, squinting into the dark basin below them. “We’ll want to clear that before we’ve got any chance o’ breakin’ the ground.”

“Right,” said Robin, reaching for a pair of gloves.

“Ye sure about this, big man?” Barclay asked Strike, who had done the same.

“I can pull up nettles, for Christ’s sake,” said Strike irritably.

“Bring the ax, Robin,” said Barclay, grabbing the mattock and a pinchbar. “Some o’ those bushes’ll need hacked down.”

The three of them slid and stumbled down the steep side of the dell and set to work. For nearly an hour they hacked at sinewy branches and tugged up nettles, occasionally swapping tools or returning to the upper ground to fetch different ones.

In spite of the gathering cool of the night, Robin was soon sweating, peeling off layers as she worked. Strike, on the other hand, was devoting a considerable amount of energy to pretending that the constant bending and twisting on slippery, uneven ground wasn’t hurting the end of his stump. The darkness concealed his winces, and he was careful to rearrange his features whenever Barclay or Robin turned on the torch to check on their progress.

Physical activity was helping dispel Robin’s fear of what could be hidden beneath their feet. Perhaps, she thought, this was what it was like in the army: hard manual work and the camaraderie of your colleagues helping you focus on something other than the grisly reality of what might lie ahead. The two ex-soldiers had bent to their task methodically and without complaint except for occasional curses as stubborn roots and branches tore at fabric and flesh.

“Time tae dig,” said Barclay at last, when the bottom of the basin was as clear as they could reasonably make it. “Ye’ll need to get out of it, Strike.”

“I’ll start, Robin can take over,” said Strike. “Go on,” he said to her, “take a break, hold the torch steady for us and pass me down the fork.”

Growing up with three brothers had taught Robin valuable lessons about the male ego, and about picking her fights. Convinced that Strike’s order was dictated more by pride than by sense, she nevertheless complied, clambering up the steep side of the dell, there to sit and hold the beam of the torch steady while they worked, occasionally passing down different tools to help them remove rocks and tackle particularly hard stretches of ground.

It was a slow job. Barclay dug three times as fast as Strike, who Robin could see was immediately struggling, especially with pressing the pointed head spade down into the earth with a foot, his prosthesis being unreliable if asked to support his entire weight on the uneven ground, and excruciating when pressed down against resistant metal. Minute by minute she held off intervening, until a muttered “fuck” escaped Strike, and he bent over, grimacing in pain.

“Shall I take over?” she suggested.

“Think you’re going to have to,” he muttered ungraciously.

He dragged himself back out of the dell, trying not to put any more weight on his stump, taking the torch from a descending Robin and holding it steady for the other two as they worked, the end of his stump throbbing and, he suspected, rubbed raw.

Barclay had created a short channel a couple of feet deep before he took his first break, clambering out of the hole to fetch a bottle of water from his kit bag. While he drank and Robin took a rest, leaning on the handle of her spade, the sound of barking reached them again. Barclay squinted towards the unseen Chiswell House.

“What kind of dogs has she got in there?” he asked.

“Old Lab and a yappy bastard of a terrier,” said Strike.

“Don’t like our chances if she lets them oot,” said Barclay, wiping his mouth on his arm. “Terrier’ll get straight through those bushes. They’ve got fuckin’ good hearin’, terriers.”

“Better hope she doesn’t let them out, then,” said Strike, but he added, “Give it five, Robin,” and turned off the torch.

Robin, too, climbed out of the basin and accepted a fresh bottle of water from Barclay. Now that she was no longer digging, the chill made her exposed flesh creep. The fluttering and scurrying of small creatures in the grass and trees seemed extraordinarily loud in the darkness. Still the dog barked, and, distantly, Robin thought she heard a woman shout.

“Did you hear that?”

“Aye. Sounded like she was telling it to shut up,” said Barclay.

They waited. At last, the terrier stopped barking.

“Give it a few more minutes,” said Strike. “Let it fall asleep.”

They waited, the whispering of every leaf magnified in the darkness, until Robin and Barclay lowered themselves back into the dell and began to dig again.

Robin’s muscles were now begging for mercy, her palms beginning to blister beneath the gloves. The deeper they dug, the harder the job became, the soil compacted and full of rocks. Barclay’s end of the trench was considerably deeper than Robin’s.

“Let me do a bit,” Strike suggested.

“No,” she snapped, too tired to be anything but blunt. “You’ll bugger your leg completely.”

“She’s nae wrong, pal,” panted Barclay. “Gie’s another drink of water, I’m gaspin’.”

An hour later, Barclay was standing waist deep in soil and Robin’s palms were bleeding beneath the overlarge gloves, which were rubbing away layers of skin as she used the blunt end of the mattock to try and prize a heavy rock out of the ground.

“Come—on—you—bloody—thing—”

“Want a hand?” offered Strike, readying himself to descend.

“Stay there,” she told him angrily. “I’m not going to be able to help carry you back to the car, not after this—”

A final, involuntary yelp escaped her as she succeeded in overturning the small boulder. A couple of tiny, wriggling insects attached to the underside slid away from the torchlight. Strike directed the beam back on Barclay.

“Cormoran,” said Robin sharply.

“What?”

“I need light.”

Something in her voice made Barclay stop digging. Rather than direct the beam back at her, and disregarding her warning of a moment ago, Strike slid back down into the pit, landing on the loose earth. The torchlight swung around, blinding Robin for a second.

“What’ve you seen?”

“Shine it here,” she said. “On the rock.”

Barclay clambered towards them, his jeans covered from hem to pockets in soil.

Strike did as Robin asked. The three of them peered down at the encrusted surface of the rock. There, stuck to the mud, was a strand of what was plainly not vegetable matter, but wool fibers, faintly but distinctly pink.

They turned in unison to examine the indentation left in the ground where the rock had sat, Strike directing the torchlight into the hole.

“Oh, shit,” gasped Robin, and without thinking she clapped two muddy garden gloves to her face. A couple of inches of filthy material had been revealed, and in the strong beam of the torch, it, too, was pink.

“Give me that,” said Strike, tugging the mattock out of her hand.

“No—!”

But he almost pushed her aside. By the deflected torchlight she could see his expression, forbidding, furious, as though the pink blanket had grievously wronged him, as though he had suffered a personal affront.