“Neither do I. But… on his behalf… and for Rowena’s sake… thank you for not taking it further.”

Silence and distance crystallized in the still air. Her mouth didn’t so much as quiver. And what there might be in her eyes to reveal her real opinion of me I couldn’t see. “Would you… like a drink?”

“No. I can’t stay.”

“Not even for a few minutes?”

“What would be the point?”

“I don’t know. I just…”

“Why did you say those things to Seymour, Robin? I’d like to know that much at least. I really would.” Even if her face remained a mask, her voice had now, at last, betrayed a hint of emotion. “I mean, after making us think of you as a friend, after assuring us of your best intentions… After all that. Why?”

“What I said was true.”

“And that excuses everything, does it? That makes Rowena’s death worthwhile?”

“No. Of course it doesn’t.”

“What about Sophie? I gathered from Bella you’d undertaken to find out what she thought her few minutes of character assassination were likely to achieve. I can’t believe she pretends to have been speaking the truth.”

“She does, as a matter of fact.”

“I see.” Sarah sighed and gazed past me up at the hills behind the house, their wooded slopes shimmering in the heat. “Good old Sophie.”

“Sarah-” She looked round at me, daring me, I sensed, to make some attempt at mitigation or apology, almost craving the opportunity to reject whichever I offered. But I knew better than to try. Whatever blame attached to me for Rowena’s death I meant to accept. It was my secret act of mourning. But blame for something even worse than a despairing dive from Clifton Suspension Bridge hovered at the margins of my thoughts. Which Sarah might just be able to help me corner at last. “Sophie claims your mother told her a few weeks before her death that she was planning to leave your father.” No reaction. No response. Just the same blank grief-sapped stare. “You once told me something similar yourself. As a theory. As a suspicion you’d formed. Sophie seemed rather more definite.”

“Did she?”

“But she didn’t know who your mother was planning to leave your father for. Who the man in her life was. Nor did you, as I recall.”

“Why does there have to have been a man?”

“No reason, I suppose. Except… Lying in hospital most of this week’s given me time to think. And to remember. Ten days after the murders, I drove up to Kington with Bella. We had lunch with Henley Bantock. He told you about it. You said so when you wrote to me in Brussels. You’d been there the same day.”

“What of it?”

“So had somebody else. He nearly drove into Bella and me in Butterbur Lane. Did Henley mention him to you? He did to us.”

“I don’t think so. Why?”

“Because the driver of the car was obviously extremely upset. He might have been… well, he could have been…”

“The man in Mummy’s life?”

“Well, he could, couldn’t he?”

“Yes. I suppose he could. So, who was he?”

“I don’t know. But it occurred to me you might. If I described him. As a friend or acquaintance of your mother. Of your father too, perhaps. A neighbour. A colleague. An art collector. Something like that. He was-let’s see-a chap in his fifties, with thick silver-grey hair. Round face. Chubby. Well, more flabby really. As if he’d lost weight recently. Of course, it was only-” I stopped. Sarah’s lips had parted in surprise. She plucked off her dark glasses and stared at me intently. “You know him?”

“Maybe. What sort of car was he driving?”

“A Volvo estate.”

“Colour?”

“Maroon.”

“It has to be, then.”

“You do know him?”

“Yes. I think I do. But it can’t be. Not really. Not him and Mummy.”

“Who is he?”

“I’m surprised neither you nor Bella’s met him. But I suppose there’s no reason why you should have. He didn’t come to Rowena’s wedding. Or to Mummy’s funeral. That seemed odd at the time. Disrespectful almost. Even though you could say he was represented by Sophie. But perhaps he was afraid of-”

“What do you mean by represented?”

“She’s married to him, Robin. The man you’ve described is Howard Marsden. Sophie’s husband. To the life.”

It became clear to me in an instant. As if I’d crept into a darkened room and stumbled around in the gloom, navigating by touch and guesswork. Only for the light to be suddenly switched on. And for me to find myself not where I thought at all. Howard Marsden. Sophie’s husband. And Louise’s lover. Yes, of course. It made sense. Sophie must have known all along. So now she was taking her revenge. On Louise by tarnishing her reputation to the best of her ability. And on Howard by cuckolding him at the first opportunity. If I was the first. Her story about the “perfect stranger”; her claim to believe I was the man in question; her expression of doubt about Naylor’s guilt: all were artful pretences designed with a particular purpose in mind. And I didn’t flatter myself that my seduction was it. No, no. Sophie was playing a deeper game, in which her husband’s total humiliation was the goal. He couldn’t object to her infidelity without being told that what was sauce for the gander…

“So that’s why Sophie wants to hurt us,” murmured Sarah.

“Looks like it.”

“Oh God. What a mess.”

“I don’t suppose she meant to harm Rowena. Your mother’s good name was what she wanted to-”

“But you can’t pick and choose when you start this sort of thing. You can’t be sure of all the consequences.”

“No. As Rowena once told me, there are too many variables in life to predict any outcome with precision.”

Sarah shook her head and rubbed the sides of her nose where the dark glasses had been resting. She looked suddenly tired. “Can I sit down, Robin? I think I would like a drink after all.”

I fetched another chair as well as a drink and we sat there in the garden together for an hour or more as the heat of afternoon turned towards the cool of evening. Our mutual dismay had lowered our defences. Allowing, if not a reconciliation between us, at least a rapprochement. As Sarah admitted, she’d made her own misjudgements. By trying to keep Rowena insulated from reality. By failing to foresee what she’d do if she found out she’d been deceived. The irony was that, even if I’d not given Sarah the video, she’d probably have recorded the programme herself while she was out with Paul and Rowena. Rowena had simply read her sister’s mind more acutely than she’d been given credit for.

As for the act of suicide itself, maybe that didn’t have the clear and simple motive it had comforted Sarah to believe. Why had Rowena not told Paul she was pregnant? Why had she seemed so depressed? Because motherhood wasn’t necessarily the future she had in her sights? Yet it had been going to arrive whether she liked it or not. Until the shock of her mother’s rewritten past had given her a way out. And she’d yielded to temptation.

“I wonder if that’s why Paul lashed out at you. Because he’s afraid that might be the truth of it. He won’t admit it, of course. I wouldn’t ask him to. But I think it may be there, even so.”

“How is he now?”

“Subdued. Self-controlled. A little remorseful, I think. A little ashamed of what he did. But don’t expect an apology. Or any kind of thanks for not preferring charges. It isn’t in his nature.”

“Will you tell him about Howard Marsden?”

“Oh yes. If Rowena’s death has taught me anything, it’s the danger of secrecy.”

“And your father?”

“He may already know. He may always have known. Maybe it’s what was in the note he destroyed.”

“But if not?”

“I’ll leave Bella to solve the problem. Isn’t that what stepmothers are for?”

“Will you let Sophie know we’ve found out?”

“Only if she asks. Which is unlikely, since I don’t intend to seek her company. Or her husband’s.”