German Concentration Camps Factual Survey is the official British documentary film on the Nazi concentration camps, based on footage shot by the Allied forces in 1945.The film was produced by Sidney Bernstein, then with the British Ministry of Information, with Alfred Hitchcock acting as a "treatment advisor". The script was written by Richard Crossman and Colin Wills. Soviet filmmaker Sergei Nolbandov was production supervisor.The project was abandoned in September 1945, and the film was left unfinished for nearly seventy years. The film's restoration was completed by film scholars at the Imperial War Museum. The finished film had its world premiere early in 2014 at the Berlin Film Festival, and was shown in a limited number of venues in 2015. It was released in North America in 2017.The British government shelved the film without showing it to the public, and questions have been raised about the extent to which political considerations, such as British concern about Zionism or changes in German occupation policy, may have played in the film being withheld.