Seventy-five years after its publication, "The Diary of Anne Frank" remains among the most widely-read books in the world. Blinkering between hope and despair, the account of a Jewish teenager's life in hiding in an annex behind an Amsterdam warehouse, gave voice and a face to millions of victims of the Nazi genocide, yet one question has gone stubbornly unanswered all these years: who alerted the Nazi search team, in 1944, to Anne Frank and her family's hiding place? Two Dutch police inquiries and countless historians have come up with theories, but no firm conclusion. 

Then, in 2016, a team of investigators, led by a veteran FBI agent, decided to bring modern crime-solving techniques and technology to this cold case. And now, they believe they have an answer—one we'll share with you tonight—to a question that's bedeviled historians, and haunted Holland: who was responsible for the betrayal?