When Ivy, an Edwardian belle, begins to like Miles, a wealthy gentleman, she is unsure of what to do with her husband, Jervis, and her lover, Dr. Roger. She then hatches a plan to get rid of them both.

In order to help bring Nazis to justice, U.S. government agent T.R. Devlin recruits Alicia Huberman, the American daughter of a convicted German war criminal, as a spy. As they begin to fall for one another, Alicia is instructed to win the affections of Alexander Sebastian, a Nazi hiding out in Brazil. When Sebastian becomes serious about his relationship with Alicia, the stakes get higher, and Devlin must watch her slip further undercover.