When Allied forces liberated Nazi concentration camps in 1944-45, the horrific scenes they encountered were captured by military and newsreel cameramen, exposing the full extent of the atrocities for the first time. Utilizing footage from British, Soviet, and American sources, Sidney Bernstein of the Ministry of Information, who would later establish Granada Television, sought to produce a documentary that would serve as irrefutable evidence of the Nazis’ horrific crimes. He enlisted a team of British experts, including editor Stewart McAllister, writer and future cabinet minister Richard Crossman, and his friend Alfred Hitchcock as a treatment advisor. Despite initial backing from the British and US governments, the project was shelved. Now, 70 years later, it has been restored and completed by the Imperial War Museums under its original title, “German Concentration Camps Factual Survey.”