As he boarded the plane and stowed his bag under the seat, he felt oddly relieved to have shared with Malik some of the details of his own torturous history, even if it meant crossing a sacrosanct boundary to unburden himself to a patient. If nothing else, it might appear to an outsider as a macabre form of one-upmanship. You think your father was a monster? Well, listen to this. Before today, he’d not told his story to a single soul. Even Sophie, his oft-mourned love, had been spared. What would have been the point in tainting her with the horror of his father’s crimes? Malik Sayid might be one of the very few he’d met in his life who understood the cost of dragging a monstrous inheritance behind him.

Though saying the words out loud would do little to relieve the crushing weight of his legacy, and the horrific acts perpetrated by his father. The man who’d given him life was none other than the commandant of a notorious Nazi concentration camp in Poland. Fuelled by his allegiance to a murderous regime, a man who’d orchestrated the deaths of some 900,000 men, women and children. Rounded up like swine, stripped of their dignity, gassed like vermin.

And Gessen’s mother. How could she have stood by such a repellent creature? As a half-Jewish woman, registered as a Mischling, the Nazis’ insidious label to keep non-Aryans from government positions, how was it possible she could stand by as her own people perished? Those photos he’d found in his father’s desk as a child and been so charmed by. It was only later he understood that the eyes of the children were dead. Clouded by the foregone knowledge of the future that awaited them, as the clock ticked the minutes to the end.

When he, as little Anton, had first opened his eyes, it was to the tremulous purple blossoms of the jacarandas lining their quiet street on the outskirts of Buenos Aires. Five years earlier, his father had deftly eluded his fate at Nuremberg by changing his name and boarding a passenger ship, with his pregnant wife and daughters in tow, to start a new life in South America.

Of all this, Gessen knew nothing for years. Two days after his father was plucked off the streets and extradited to Germany, his mother fled with her son to Switzerland where she later left her six-year-old boy in the care of friends. Bewildered by the sudden loss of his parents, he’d been fed all kinds of lies by his adoptive family, that his father passed away from illness, and his mother died of grief.