The last of four films in four successive years that Thelma Ritter was nominated for the Best Supporting Actress Oscar. This film follows nominations for All About Eve (1950), The Mating Season (1951) and With a Song in My Heart (1952).
After seeing a preview of the film, FBI Director J. Edgar Hoover demanded a meeting with studio boss Darryl F. Zanuck and the film's director/writer Samuel Fuller. He objected to the unpatriotic nature of Skip, even when he realizes he's dealing with communists. Zanuck refused to make any changes to the film, backing Fuller. This ended the studio's close relationship with the FBI and all references to the agency were removed from the film's advertising, posters, and lobby cards.
Marilyn Monroe sat in on a rehearsal and actually read for the role of Candy. While writer/director Samuel Fuller liked her very much, he said she was wrong for the part, telling her that her "overwhelming sensuality" was wrong for the story.
According to Samuel Fuller's autobiography, "A Third Face," Betty Grable had wanted the role of Candy and demanded that there be a dance number in the film. Fuller refused. Grable then said she would do the film without the dance number, but by that point Fuller had been rehearsing with Jean Peters and didn't want to lose her for the role.
Alan Reed, who played an uncredited detective, is better known as the cartoon voice of Fred Flintstone.