He left Magda in the kitchen and climbed the stairs to find more of the cheap flat-pack furniture in the bedroom, decorated in the style of a Marriott off the motorway, circa 1984. Beige curtains. A carpet the texture and colour of porridge. On the nightstand, a travel-sized clock ticked the minutes away. The only odd note was the heavy brass bolt fixed to the inside of the door. Did Vidor lock himself in at night? Against what, or whom? The neighbourhood seemed innocuous enough. It wasn’t as if bands of thieves and cutthroats were menacing this quiet corner of Cambridge.

He stepped into the bathroom to peek in the medicine cabinet. So much you could learn about a person by what they kept in there and how it was arranged. A steel razor and packet of extra blades. A bar of yellow soap from a Cambridge shop, still wrapped in paper. Gessen lifted it to his nose and sniffed. A faint scent of sandalwood and myrrh, reminiscent of an Eastern bazaar. A glass and toothbrush. A bottle of aspirin. No other drugs that he could see.

He pulled open the curtains and looked down into the garden where the feral cat was sunning itself on the flagstones. Gessen turned away to examine the room, so silent he could almost hear the house settling on its foundation. The abode of a solitary man, alone in the world. No photos of family, at least none that he’d seen. No evidence of the four sisters, or the beloved mother and heroic father. What of them? Their likenesses must be immortalised somewhere. Perhaps in a photo album tucked away in a cupboard. Or had a family rupture occurred sometime in the past? Vidor once let slip that his eldest sister had emigrated to North America long ago, but it wasn’t clear whether he’d meant the States or Canada.

His father was long dead, apparently, if Vidor had told the truth. And if his mother were still alive, she’d be in her late eighties, at least. Vidor alone, tout seul, as if he’d sprung from the bowels of the earth, with no ancestors or history behind him.

When he pushed open the door of Vidor’s study, he stopped dead. In contrast to the rest of the house, it looked as though a cyclone had blown through. Books and paperwork were spilled across the desk in a chaotic jumble. An open drawer was bursting with folders and thick with papers. A quick search through the files revealed nothing of interest. At the sound of a creak on the stairs he yanked his hand away, slicing his thumb on a jagged piece of metal. Blood flowed from the cut, but with nothing else to staunch the bleeding he hastily pressed a Post-It note against the wound.