A “gripping” (Kati Marton, author of The Chancellor) historical investigation and family memoir that intertwines the iconic narrative of Anne Frank with the untold story of Bep Voskuijl, her protector and closest confidante in the Annex, bringing us closer to understanding one of the great secrets of World War II.

Anne Frank’s life has been studied by many scholars, but the story of Bep Voskuijl has remained untold, until now. As the youngest of the five Dutch people who hid the Frank family, Bep was Anne’s closest confidante during the 761 excruciating days she spent hidden in the Secret Annex. Bep, who was just twenty-three when the Franks went into hiding, risking her life to protect them, plunging into Amsterdam’s black market to source food and medicine for people who officially didn’t exist under the noses of German soldiers and Dutch spies. In those cramped quarters, Bep and Anne’s friendship bloomed through deep conversations, shared meals, and a youthful understanding.

Told by her own son, The Last Secrets of Anne Frank intertwines the story of Bep and her sister Nelly with Anne’s iconic narrative. Nelly’s name may have been scrubbed from Anne’s published diary, but Joop van Wijk-Voskuijl and Jeroen De Bruyn expose details about her collaboration with the Nazis, a deeply held family secret. After the war, Bep tried to bury her memories just as the Secret Annex was becoming world famous as a symbol of resistance to the Nazi horrors. She never got over losing Anne nor could Bep put to rest the horrifying suspicion that those in the Annex had been betrayed by her own flesh and blood.

“Part biography, part whodunit” (The Wall Street Journal), this is a story about those caught in between the Jewish victims and Nazi persecutors, and the moral ambiguities and hard choices faced by ordinary families like the Voskuijls, in which collaborators and resistors often lived under the same roof.

Beautifully written and unsettlingly suspenseful, The Last Secrets of Anne Frank will show the Secret Annex as we’ve never seen it before. And it provides a powerful understanding of how historical trauma is inherited from one generation to the next and how sometimes keeping a secret hurts far more than revealing a shameful truth.