“Mother was . . . alive. She was dark and bright and very funny—she had a much quicker sense of humour than Father did, and the infectious giggle of a child. She was orderly—she didn't mind if things were turned upside-down in the course of the day, but she liked to see them restored to their places eventually. She was a natural teacher, knew how to present things so they caught the imagination of a child. She taught us both Hebrew, through the Bible, and with me she used an analytical approach—how slight changes in grammar affect meaning, for example—whereas with my brother she concentrated on the mathematics. She and his maths tutor worked out a system for integrating math problems and Torah studies, using the Bible to build problems in calculus and such; I never did understand it. Looking back, she might have been worried that Levi would turn his back on his faith, and wanted to ensure that Torah was in his bones from early on.”

“Your brother was a brilliant boy, you told me.”

“Levi was a genius, an extraordinary mind.” I stared out over the water, white streaks appearing in the darkness as each wave peaked, then vanished with the crash of the surf. “He had three tutors. One for maths, one for Torah and Talmud, and one for everything else—he didn't care for history and English, but he could memorise anything, which served the same purpose as actual learning as far as he was concerned. I hated him, sometimes. I loved him, too, but he tended to dominate life, rather. It was always lovely to get one of the parents to myself. So relaxed. Actually, I think my parents were almost frightened by him. Certainly daunted—I would catch my father looking at Levi sometimes, as if wondering what sort of creature this was in his house.”

I stood, brushing the sand from my skirt. “That's about all I have of them, vague outlines coupled with specific incidents. But I believe you'd have liked them, Holmes. I'm very sorry you never had a chance to meet them.

“And now I think our driver may be getting nervous, that we've fallen into the sea.”

On Wednesday morning, I left Holmes at the front desk, puzzling the affable Mr Auberon with enquiries about glass-shops, and went to Norbert's office. Before we got started on the day's mountain of paperwork, I asked him about the Chinese couple employed on the property. He knew nothing about them, but said he would look into it. Then I asked how many sets of house keys he had.

“Just the one I gave you,” he answered. “I do have another complete set, but it's down the Peninsula with my other papers. Do you wish me to have it sent up for you?”

“No, I just wondered. It appeared as if we'd had a visitor in the house recently.”