‘You are my guest, monsieur,’ she said, showing him where he could hang his coat. She disappeared and returned with a bright turquoise hand towel to dry his hair. Awash with a pearly light, the high-ceilinged main room was plainly furnished. The dominant feature, a grand piano, in the far corner by the window, gleamed with polish. The faint whoosh of traffic filtered in from the street. On a bookshelf, a brass carriage clock ticked the minutes. Otherwise, it was silent, and the air filled with the weight of expectation.

She disappeared into the back of the flat and returned with a silver pot of coffee on a tray and a plate of oval buttery biscuits, the kind sold in those little shops in Brittany. He remembered them from the time he’d fled Paris and travelled to the Finistère, not long after he’d broken things off with Sophie. Since then, Gessen had never returned to that part of France. Even the smell of the biscuits brought back the familiar nausea, but he took one to be polite and placed it on the edge of his plate.

‘What a shock it was to get your letter,’ she said, pouring the coffee into white demi-tasse cups. ‘When I was a girl, our family lived in this same quartier, not far from here. A few months after I married, I moved to Lyon with my husband, but after he died I returned to Paris. It was a stroke of luck to have found this flat. This neighbourhood has always felt like home to me. My three sisters moved abroad years ago, seeking their fortunes elsewhere. Strange, isn’t it, how children born of the same parents can turn out to be so different from one another?’

Gessen perched awkwardly on a cream-coloured settee, while Madame Chabon reclined in the shadowy recesses of a yellow wingback chair. On the table between them lay a bulky portfolio with a faux leather cover stamped with gold lettering. It looked like a photo album or scrapbook, and he could hardly contain his excitement. Perhaps this was it: proof that this woman’s brother, Vidor Sovàny, was the man known to the world as Vidor Kiraly. In which case, the young Vidor must have faked his death and adopted a new identity.