LONDON — On the morning of June 23, 1940, 12-year-old Ninette Dreyfus’s family learned that Hitler had forced France into a humiliating armistice the previous evening. Her father’s reaction to the news was visceral and physical. Edgar Dreyfus collapsed on the stairs, suffering an asthma attack and struggling to breathe. “I had never seen him show weakness before. For a moment, I feared he was going to die,” Ninette later recalled. “The whole world of my childhood was falling apart.” But unbeknownst to Ninette, her father, or France’s Jews, much worse was to come. Released in paperback in the UK...