The film was shown to all new Royal Navy recruits after it was released to give them an idea and an impression of what life in the Navy was like.
The Hays office tried to delete the words "God", "hell", "damn", and "bastard" from the American release. Uproar from England forced the office to back down on everything except "bastard".
The idea for the film sprang out of Noel Coward's friendship with Winston Churchill (the two often painted together) and his desire to do something more substantial than urbane comedies to help the war effort for his friend. Coward acutely felt that with the coming of war, the world of which he wrote - bright young things scampering around drawing rooms - was a world that no longer existed.
The role of Lavinia Kinross was originally intended for 5 year old Anna Massey, as her brother Daniel Massey had been cast as her film brother Bobby Kinross. According to her memoirs however she screamed so much at the audition that the role had to be recast.
There was a tragedy during the shooting of the film, during a relatively straightforward special effects scene of an explosion in a gun turret. After the first take, Lean (Coward wasn't present) was dissatisfied. Chief electrician Jock Dymore, keen to get the scene wrapped before lunch, climbed onto the set with a bottle full of the flash-powder used for the explosive effect. The containers they were using were still white hot from the first take, and the resulting blast killed Dymore and seriously injured two others.
This film's dedication states: "This film is dedicated to the Royal Navy whereupon under the good providence of God, the wealth, safety and strength of the kingdom chiefly depend."
This was Richard Attenborough's first screen role (he had been recommended for his small but important part by director turned agent Albert Parker). He is uncredited purely because of an oversight.
When dive bombers fire on the survivors clinging to a life raft, the effect of the strafing fire hitting the water was achieved by blowing gusts of air into submerged condoms. These would then float to surface after the director had shouted cut.
When the film opened in September 1942, the Admiralty praised it for its authentic portrayal of navy life.