Verboten! (1959)

A young American serviceman stationed in Germany after the fall of the Third Reich jeopardizes his position with the Marshall Plan relief effort by breaking the non-fraternization rule and falling in love with a young German woman. He uses his position to obtain food and luxuries for her that are in short supply, and all seems to be going well for the couple. What he doesn't realize is that the Werewolves, the Nazi guerrilla movement, has plans in which he features heavily.