AMSTERDAM — Hiding from the Gestapo in a secret annex of her father’s warehouse in Amsterdam during World War II, Anne Frank heard a little knock on the wall. She could not be sure who or what it was, and it frightened her.

She was right to be scared: Just months later, on Aug. 4, 1944, the police discovered the hide-out during a raid and arrested her and seven others living behind a movable bookcase. All but Otto Frank, the diarist’s father, and later the editor of “The Diary of a Young Girl,” perished in Nazi death camps.

Who gave them up has remained a mystery. Now, almost 75 years later, a team of experts led by a retired F.B.I. agent is bringing modern forensic science and criminology to bear in hopes of solving one of history’s most famous cold case files.

“We will put special emphasis on new leads,” said the retired special agent, Vince Pankoke, 59, who is leading the effort. “We need to verify stories as they come in, and we know that is going to lead to further investigation.”