During the Second World War met David Halloran (Harrison Ford), an American pilot who is stationed in London the English nurse Margaret Sellinger (Lesley-Anne Down).It is love at first sight for both of them, although Margaret is already married, which they keep secret for her American lover. Lieutenant Haloran is sent on a secret mission along with secret agent Paul Sellinger (Christopher Plummer), the husband of Margaret. However, their plane is shot down over France and if only two survivors they must work together to accomplish their mission and to get back in London. Dressed as German SS officers they succeed ultimately in return. As Margaret her wounded man is look it up in the hospital she sees her lover for the last time and he takes leave of her.