Patrick "The Ear" Muldoon, a professional safecracker, passes on his skills to his daughter Peggy. However, after reading Ralph Waldo Emerson's books, Peggy decides to forego a life of crime, after pulling one last job. Unfortunately, she's arrested for that crime and sent to prison for two years. When she gets out of prison she moves to California and meets Robert Benton, who works in a local bank. Theu marry and are living happily--until Peggy's old gang shows up and threatens to tell her husband about her past unless she helps them crack the safe in his bank.