“We’d already been through it once when they found the other body, the one in Alexandra Lake,” said Cynthia.

“Susan Meyer,” muttered Robin.

“Roy was shown pictures, both times… And then this phone call, coming right after he’d had to… for the second time… it was…”

Cynthia was suddenly crying, not like Oonagh Kennedy, with her head up and tears sparkling on her cheeks, but hunched over the table, hiding her face, her shaking hands supporting her forehead.

“I’m so sorry,” she sobbed. “I knew this would be awful… we never talk about her any—any more… I’m sorry…”

She sobbed for a few more seconds, then forced herself to look up again, her large eyes now pink and wet.

“Roy wanted to believe it had been Margot on the phone. He kept saying ‘Are you sure, are you sure, it didn’t sound like her?’ He was on tenterhooks while the police traced the call…

“You’re being very polite,” she said, and her laugh this time was slightly hysterical, “but I know what you want to know, and what Anna wants to know, too, even though I’ve told her and told her… There was nothing going on between me and Roy before Margot disappeared, and not for four years afterward… Did she tell you that Roy and I are related?”

She said it as though forcing herself to say it, although a third cousin was not, after all, a very close relationship. But Robin, thinking of Roy’s bleeding disorder, wondered whether the Phippses, like the Romanovs, mightn’t be well advised not to marry their cousins.

“Yes, she did,” said Strike.

“I was sick of the sound of his name before I went to work for them, actually. It was all, ‘Just look at Cousin Roy, with all his health problems, getting into Imperial College and studying medicine. If you’d only work harder, Cynthia…’ I used to hate the very idea of him, hahaha!”

Robin recalled the picture of young Roy in the press: the sensitive face, the floppy hair, the poet’s eyes. Many women found injury and illness romantic in a handsome man. Hadn’t Matthew, in his worst effusions of jealousy against Strike, invoked his amputated leg, the warrior’s wound against which he, whole-bodied and fit, felt unable to compete?

“You might not believe this, but as far as I was concerned at seventeen, the best thing about Roy was Margot! No, I thought she was marvelous, so—so fashionable and, you know, lots of opinions and things…

“She asked me over for dinner, after she heard I plowed all my exams. Well, I hero-worshipped her, so I was thrilled. I poured my heart out, told her I couldn’t face resits, I just wanted to get out in the real world and earn my own money. And she said, ‘Look, you’re wonderful with children, how about coming and looking after my baby when I go back to work? I’ll get Roy to do up the rooms over the garage for you.’

“My parents were livid,” said Cynthia, with another brave but unsuccessful stab at a laugh. “They were furious with her, and Roy, although actually, he didn’t want me there in the first place, because he wanted Margot to stay at home and look after Anna herself. Mummy and Daddy said she was just after cheap labor. These days I do see it more from their point of view. I’m not sure I’d have been delighted if a woman had persuaded one of my girls to leave school and move in with them, and look after their baby. But no, I loved Margot. I was excited.”

Cynthia fell silent for a moment, a faraway look in her doleful eyes, and Robin wondered whether she was thinking about the huge and unalterable consequences of accepting the job as nanny, which instead of being a springboard to her own independent life had placed her in a house she would never leave, led to her raising Margot’s child as her own, sleeping with Margot’s husband, forever stuck in the shadow of the doctor she claimed to have loved. What was it like to live with an absence that huge?

“My parents wanted me to go away after Margot disappeared. They didn’t like me being alone at the house with Roy, because people were starting to gossip. There were even hints in the press, but I swear to you on the lives of my children,” said Cynthia, with a kind of dull finality, “there was nothing between Roy and me, ever, before Margot disappeared, and not for a long time afterward, either. I stayed for Anna, because I couldn’t bear to leave her… she’d become my daughter!”

She hadn’t, said the implacable voice in Robin’s head. And you should have told her so.

“Roy didn’t date anyone for a long time after Margot disappeared. Then there was a colleague at work for a while,” Cynthia’s thin face flushed again, “but it only lasted a few months. Anna didn’t like her.

“I had a kind of on-off boyfriend, but he packed me in. He said it was like dating a married woman with a child, because I put Anna and Roy first, always.

“And then I suppose…” said Cynthia shakily, one hand balled in a fist, the other clutching it, “… over time… I realized I’d fallen in love with Roy. I never dreamed he’d want to be with me, though. Margot was so clever, such a—such a big personality, and he was so much older than me, so much more intelligent and sophisticated…

“One evening, after I’d put Anna to bed, I was about to go back to my rooms and he asked me what had happened with Will, my boyfriend, and I said it was over, and he asked what had happened, and we got talking, and he said… he said, ‘You’re a very special person and you deserve far better than him.’ And then… then, we had a drink…

“That was four years after she’d disappeared,” Cynthia repeated. “I was eighteen when she vanished and I was twenty-two when Roy and I… admitted we had feelings for each other. We kept it secret, obviously. It was another three years before Roy could get a death certificate for Margot.”

“That must have been very hard,” said Strike.

Cynthia looked at him for a moment, unsmiling. She seemed to have aged since arriving at the table.

“I’ve had nightmares about Margot coming back and throwing me out of the house for nearly forty years,” she said, and she tried to laugh. “I’ve never told Roy. I don’t want to know whether he dreams about her, too. We don’t talk about her. It’s the only way to cope. We’d said everything we had to say to the police, to each other, to the rest of the family. We’d raked it all over, hours and hours of talking. ‘It’s time to close the door,’ that’s how Roy put it. He said, ‘We’ve left the door open long enough. She’s not coming back.’

“There were a couple of spiteful things said in the press, you know, when we got married. ‘Husband of vanished doctor marries young nanny.’ It’s always going to sound sordid, isn’t it? Roy said not to mind them. My parents were appalled by the whole thing. It was only when I had Jeremy that they came around.

“We never meant to mislead Anna. We were waiting… I don’t know… trying to find the right moment, to explain… but how are you supposed to do it? She used to call me ‘Mummy,’” whispered Cynthia, “she was h- happy, she was a completely happy little girl, but then those children at school told her about Margot and it ruined every—”