The film outlines the story of Kurt Gerstein, a nazi officer who was responsible for delivering Zyklon B to the German concentration camps during World War Two. Upon delivering gas to the Belzec concentration camp, Gerstein realizes the purpose of the gas, which is being used to gas prisoners and not simply 'de-louse' them as he had been told. Upon realizing the evil he has facilitated, Gerstein vows to expose the Holocaust and attempts to do so through meetings with prominent diplomats of Allied or neutral countries. Though few believe him, Gerstein ultimately negotiates a surrender to the French, where he spends years writing The Gerstein Report, a full disclosure of the Nazi's extermination camp system.