Anecdotes

For the scene in which a street is wiped out by a V2, the filmmakers destroyed a row of flats which were slated for demolition.

Hannah Reitsch (Barbara Rütting) was a real-life person. Reitsch was a German aviatrix, and at one time, Adolf Hitler's personal pilot. During the Battle of Berlin, Reitsch attempted to persuade Hitler to escape from the city in a small lightweight Fieseler Storch airplane.

As Sophia Loren was blacklisted in Arab countries because of her portrayal of a Jewish woman who survived a concentration camp, in Daniel Mann's Judith (1966), which was shot in Israel, this movie was shown in Beirut, Lebanon with all of the Loren bits removed. The movie poster was changed, and her name removed from the top billing. This movie was shown at the Cinema Strand and the audience never suspected Loren was part of this production.

MGM executives did not know the German characters would be speaking German (with subtitles) until they saw the rough cut. They wanted to have the German dialogue dubbed into English, but Director Michael Anderson persuaded them to keep the subtitled dialogue.

Duncan Sandys (Richard Johnson) was a real-life person. Sandys was Chairman of the British War Cabinet Committee for the Defence against German rockets and flying bombs. He was the son-in-law of British wartime Prime Minister, Sir Winston Churchill and was wounded during the in Norway in 1941, which resulted in him having a permanent limp.