Geraldine Schwarz's family never discussed what happened in the war. Neither heroes nor villains, her German grandparents were merely the 'Mitlaufer' - those who followed the current. They just wanted to forget, to bury it all under the wreckage of the Third Reich. But decades later when, delving through filing cabinets in the basement of their apartment building in Mannheim, Geraldine discovers that her grandfather Karl profited from the forced 'Aryanisation' of Jewish businesses, she is compelled to investigate her ancestors' past. How guilty were they? Weaving together the threads of three generations of family history - from Nazi Germany to Vichy France - with that of Europe's process of postwar reckoning, Schwarz explores how millions were seduced by ideology, how they were overcome by a fog of denial after the war and how, eventually, they confronted the past. In doing so, she asks: what makes us become complicit? How should nations deal with collective guilt? And, amid the rise of extremism today, how do we ensure we remember?