Watch Captain Carey, U.S.A.

"Captain Carey, U.S.A." (1950) is also known as "After Midnight" and "O.S.S." It was based on a novel called "No Surrender." The title character is an agent of the U.S. Office of Strategic Services (which later became the C.I.A.) who was one of the few survivors of a mission that had gone fatally awry because of a betrayal from the inside. He has now returned to Italy to track down the traitor.