The Battle of the Heavy Water

Operation Swallow: The Battle for Heavy Water (original title: Kampen om tungtvannet, French title: La Bataille de l'eau lourde) is a Norwegian-French film from 1948. The story is based on the best known commando raid in Norway during World War II, where the resistance group Norwegian Independent Company 1 destroyed the heavy water plant at Vemork in Telemark in February 1943. The film is basically a reconstruction of real events, a docudrama, with many of the participants playing themselves in the film. It was filmed on location in Norway.

Synopsis: Wikipedia, CC BY-SA 4.0