View Hitchcock's newsreel documentary, "Night Will Fall", commemorating 70th anniversary of liberation of concentration camps;

When Auschwitz and other camps were liberated, the British army sent along a film unit. With the help of supervising director Alfred Hitchcock, the shocking footage was meant for a documentary called German Concentration Camps Factual Survey. However, as the war came to a close, the governments that had once supported exposing German crimes had a new interest in reconciliation and plans for the film were scrapped.

70 years later, a new documentary, Night Will Fall, tells the story of how the footage came to be, and what happened to it. Night Will Fall premieres today on HBO.

Watch clips from Alfred Hitchcock's Holocaust Documentary, Night Will Fall, here: