Would it be impertinent, considering the family’s tragic loss, to ask her to send him a photo? At least the portrait of the Sovàny family was coming into focus. But if his Vidor Kiraly turned out to be Renata Thompson’s long-lost brother, Vidor Sovàny, it would be a fantastic coincidence. Even if it were true, why would Vidor have changed his surname to his mother’s maiden name, and when? Before or after his disappearance? It seemed horribly cruel to let his family believe he had died.

In his years as a psychiatrist, Gessen had come across many people who had spurned their families to make a new start. But if that were Vidor’s intention, why relinquish the name of the man he claimed to hold dearly in his heart? To escape detection and start a new life in England, free from the mother and sisters who professed to love him? Or perhaps Vidor unconsciously blamed his father for the betrayal at the border. To a six-year-old, it would have seemed a monstrous act to leave the family to fend for themselves.

He closed his eyes, calling up the image of Vidor raging at the man in Copenhagen. Though he’d been largely incoherent, a witness was able to identify two words in the stream of invective: monster and dead. Perhaps Vidor, in a break with reality, had confused a strange man with his father. And the voice spewing forth was that of a grieving and terrified young boy, shouting at the man who’d abandoned his family in their time of need. With Vidor blocking any attempt to uncover facets of his psyche, Gessen would have to get the information some other way. At least he had a lead on Vidor’s original surname. If – and it was a very big ‘if’ – this woman’s brother was the same Vidor who’d landed in his clinic.

That Renata Thompson’s brother had vanished without a trace lent another twist to the story. If he’d intentionally dropped off the radar, the name change would cover his tracks. Armed with a new lead, Gessen could track down others who’d known Vidor Sovàny in Paris. Teachers, friends, neighbours.