The apartment house at Adalbertstrasse 68 was one of the few in the fashionable district of Schwabing yet to be overrun by Munich’s noisy and growing professional elite. Wedged between two red brick buildings that exuded prewar charm, No. 68 seemed rather like an ugly younger stepsister. Her façade was a cracked beige stucco, her form squat and graceless. As a result her suitors were a tenuous community of students, artists, anarchists, and unrepentant punk rockers, all presided over by an authoritarian caretaker named Frau Ratzinger, who, it was rumored, had been living in the original apartment house at No. 68 when it was leveled by an Allied bomb. Neighborhood activists derided the building as an eyesore in need of gentrification. Defenders said it exemplified the very sort of Bohemian arrogance that had once made Schwabing the Montmartre of Germany, the Schwabing of Hesse and Mann and Lenin. And Adolf Hitler, the professor working in the second-floor window might have been tempted to add, but few in the old neighborhood liked to be reminded of the fact that the young Austrian outcast had once found inspiration in these quiet tree-lined streets too.

To his students and colleagues, he was Herr Doktorprofessor Stern. To friends in the neighborhood he was just Benjamin; to the occasional visitor from home, he was Binyamin. In an anonymous stone-and-glass office complex in the north of Tel Aviv, where a file of his youthful exploits still resided despite his pleas to have it burned, he would always be known as Beni, youngest of Ari Shamron’s wayward sons. Officially, Benjamin Stern remained a member of the faculty at Hebrew University in Jerusalem, though for the past four years he had served as visiting professor of European studies at Munich’s prestigious Ludwig-Maximilian University. It had become something of a permanent loan, which was fine with Professor Stern. In an odd twist of historical fate, life was more pleasant for a Jew these days in Germany than in Jerusalem or Tel Aviv.

The fact that his mother had survived the horrors of the Riga ghetto gave Professor Stern a certain dubious standing among the other tenants of No. 68. He was a curiosity. He was their conscience. They railed at him about the plight of the Palestinians. They gently asked him questions they dared not put to their parents and grandparents. He was their guidance counselor and trusted sage. They came to him for advice on their studies. They poured out their heart to him when they’d been dumped by a lover. They raided his fridge when they were hungry and pillaged his wallet when they were broke. Most importantly, he served as tenant spokesman in all disputes involving the dreaded Frau Ratzinger. Professor Stern was the only one in the building who did not fear her. They seemed to have a special relationship. A kinship. “It’s Stockholm Syndrome,” claimed Alex, a psychology student who lived on the top floor. “Prisoner and camp guard. Master and servant.” But it was more than that. The professor and the old woman seemed to speak the same language.

The previous year, when his book on the Wannsee Conference had become an international bestseller, Professor Stern had flirted with the idea of moving to a more stylish building, perhaps one with proper security and a view of the English Gardens. A place where the other tenants didn’t treat his flat as if it were an annex to their own. This had incited panic among the others. One evening they came to him en masse and petitioned him to stay. Promises were made. They would not steal his food, nor would they ask for loans when there was no hope of repayment. They...