In the spring of 1945, Allied forces liberating Europe found evidence of atrocities which have tortured the world’s conscience ever since. As the troops entered the German concentration camps, they made a systematic film record of what they saw. Assembled and edited that summer under the supervision of the British Ministry of Information and the American Office of War Information, some of the documentary editing was done under the direction of Alfred Hitchcock—but the film was left unfinished. FRONTLINE found it stored in a vault of London’s Imperial War Museum and, in 1985, broadcast it for the first time. Thirty years later, Memory of the Camps remains one of the most definitive and unforgettable records of the 20th century’s darkest hour.