O.S.S.

During World War II, an American spy code-named John Martin (Alan Ladd) is part of a covert operation to destroy a tunnel vital to the German army in Nazi-occupied France. During the mission, another American spy, code-named Elaine Duprez (Geraldine Fitzgerald), falls in love with John Martin, which endangers the team's mission. But as members of the Office of Strategic Services, they have an obligation to their duty, which leads one of them to a difficult decision and sacrifice.