In this fact-based film, Lt. Richard Perry (Robert Taylor), a distinguished Naval officer, is recruited by President McKinley to infiltrate a ring of thugs. Meanwhile, Richard falls for Lil Duryea (Barbara Stanwyck), but he can't tell her his true identity. When the gang is busted during a holdup, Richard lands in jail. Unfortunately, McKinley is assassinated before he can pardon the undercover man. In order to clear his name, Richard must now tell Lil that he has never been truthful with her.