“I never knew you did that!” said Anna, looking shocked.

“Of course not. You were five years old,” snapped Roy. He turned back to Strike and Robin. “Louise’s father had made his own study of Creed’s life. He’d gone to every place Creed had ever lived or worked and interviewed as many people who’d admit to knowing him. He was petitioning Merlyn-Rees, the then Home Secretary, to let him go and dig in as many of these places as possible.

“The man was half-insane,” said Roy. “I saw then what living with something like this could do to you. The obsession had taken over his entire life. He wanted buildings dismantled, walls taken down, foundations exposed. Fields where Creed might once have walked, dug up. Streams dragged, which some schoolboy friend said Creed might have once gone fishing in. Tucker was shaking as he talked, trying to get me and Wolfson, who was a lorry driver, to join him in a TV campaign. We were to chain ourselves to the railings outside Downing Street, get ourselves on the news… Tucker’s marriage had split up. He seemed on bad terms with his living children. Creed had become his whole life.”

“And you didn’t want to help?” asked Anna.

“If,” said Roy quietly, “he’d had actual evidence—any solid clue that linked Margot and Creed—”

“I’ve read you thought one of the necklaces in the basement might’ve been—”

“If you will get your information from sensationalist books, Anna—”

“Because you’ve always made it so easy for me to talk to you about my mother,” said Anna. “Haven’t you?”

“Anna,” whispered Cynthia again.

“The locket they found in Creed’s basement wasn’t Margot’s, and I should know, because I gave it to her,” said Roy. His lips trembled, and he pressed them together.

“Just a couple more questions, if you wouldn’t mind,” said Strike, before Anna could say anything else. He was determined to avert further conflict if he could. “Could we talk for a moment about Wilma, the cleaner who worked at the practice and did housework for you here, as well?”

“It was all Margot’s idea, hiring her, but she wasn’t very good,” said Roy. “The woman was having some personal difficulties and Margot thought the solution was more money. After Margot disappeared, she walked out. Never turned up again. No loss. I heard afterward she’d been sacked from the practice. Pilfering, I heard.”

“Wilma told police—”

“That there was blood on the carpet upstairs, the day Margot went missing,” interrupted Roy. From Anna and Kim’s startled expressions, Robin deduced that this was entirely new information to them.

“Yes,” said Strike.

“It was menstrual,” said Roy coldly. “Margot’s period had started overnight. There were sanitary wrappers in the bathroom, my mother told me. Wilma sponged the carpet clean. This was in the spare room, at the opposite end of the house to the marital bedroom. Margot and I were sleeping apart at that time, because of,” there was a slight hesitation, “my injury.”

“Wilma also said that she thought she’d seen you—”

“Walking across the garden,” said Roy. “It was a lie. If she saw anyone, it would have been one of the stonemasons. We were finishing the gazebo at that time,” he said, pointing toward the stone folly at the end of the fishpond.

Strike made a note and turned over a page in his notebook.

“Can either of you remember Margot talking about a man called Niccolo Ricci? He was a patient at the St. John’s practice.”

Both Roy and Cynthia shook their heads.

“What about a patient called Steven Douthwaite?”

“No,” said Roy. “But we heard about him afterward, from the press.”

“Someone at the barbecue mentioned that Margot had been sent chocolates by a patient,” said Cynthia. “That was him, wasn’t it?”

“We think so. She never talked about Douthwaite, then? Never mentioned him showing an inappropriate interest in her, or told you he was gay?”

“No,” said Roy again. “There’s such a thing as patient confidenti­ality, you know.”

“This might seem an odd question,” said Strike, “but did Margot have any scars? Specifically, on her ribcage?”

“No,” said Roy, unsettled. “Why are you asking that?”

“To exclude one possibility,” said Strike, and before they could ask for further details, he said,

“Did Margot ever tell you she’d received threatening notes?”

“Yes,” said Roy. “Well, not notes in the plural. She told me she’d got one.”

“She did?” said Strike, looking up.

“Yes. It accused her of encouraging young women into promiscuity and sin.”

“Did it threaten her?”

“I don’t know,” said Roy. “I never saw it.”

“She didn’t bring it home?”

“No,” said Roy shortly. He hesitated, then said, “We had a row about it.”

“Really?”

“Yes. There can be serious consequences,” said Roy, turning redder, “societal consequences, when you start enabling things that don’t take place in nature—”

“Are you worried she told some girl it was OK to be gay?” asked Anna, and yet again Cynthia whispered, “Anna!”

“I’m talking,” said Roy, his face congested, “about giving reckless advice that might lead to marital breakdown. I’m talking about facilitating promiscuity, behind the backs of parents. Some very angry man had sent her that note, and she never seemed to have considered—considered—”

Roy’s face worked. For a moment, it looked as though he was going to shout, but then, most unexpectedly, he burst into noisy tears.

His wife, daughter and daughter-in-law sat, stunned, in a row on the sofa; nobody, even Cynthia, went to him. Roy was suddenly crying in great heaving gulps, tears streaming down over his sunken cheeks, trying and failing to master himself, and finally speaking through the sobs.

“She—never seemed—to remember—that I couldn’t—protect her—couldn’t—do anything—if somebody tried—to hurt—because I’m a useless—bleeder… useless… bloody… bleeder…”

“Oh Dad,” whispered Anna, horrified, and she slid off the sofa and walked to her father on her knees. She tried to place her hands on his leg, but he batted her consoling hands away, shaking his head, still crying.

“No—no—I don’t deserve it—you don’t know everything—you don’t know—”

“What don’t I know?” she said, looking scared. “Dad, I know more than you think. I know about the abortion—”

“There was never—never —never an abortion!” said Roy, gulping and sobbing. “That was the one—one thing Oonagh Kennedy and I—we both knew—she’d never—never—not after you! She told me—Margot told me—after she had you—changed her views completely. Completely!”

“Then what don’t I know?” whispered Anna.