A marine wins an amateur contest and becomes a popular singer; but his success affects his relationships with his friends.
Sergeant Mike Kelly (Allen Jenkins) urges Peggy Randall (Doris Weston) to date shy Arkansas Bob Brent (Dick Powell). At a beach weenie roast Marines strike out with their girls until Bob sings "You Can't Run Away from Me Tonight." Mike raises money from the Marines for Bob to go to New York for an amateur contest with Peggy. Her singing is rejected; but Bob sings "Cause My Baby Says It's So" and is well received. Fowler (Addison Richards) tells Aeneas Phinney (Hugh Herbert) to get Bob, who signs a contract with Peggy as his secretary. Phinney gets five hundred women to mob Bob. Actress Helen Young (Marcia Ralston) tells Phinney she wants to see Bob. Helen kisses Bob and keeps him busy. Peggy tells Helen to vamp only in her movies. Bob gets fed up with Helen and tells her to get out. Two Marines tell Bob that he was transferred to Shanghai and is late.
Bob joins his unit but says he is not going to China. The Marines feel he is a snob, and Mike orders him to swab the deck. Bob sails on a different boat in a luxury suite with Peggy, Mike, and Slim (Lee Dixon). Ma Marine (Jane Darwell) meets the conceited "Singing Marine." At a benefit Bob sings "The Lady Who Couldn't Be Kissed" with Peggy, and Slim tap dances. Bob and Peggy sing "You Can't Run Away from Me Tonight," and Bob kisses her; but then he kisses others.
In Shanghai Phinney tells Bob that he used his $50,000 to buy a night-club. Bob toasts the British empire and China. Dopey (Guinn Williams) and Slim take Bob from his bed to the captain. Bob calls Fowler that he is confined to quarters; but Bob sings by telephone until the captain comes in and arrests him. Chang asks Ma for her back-rent. Peggy applies for a job and sings "I Know Now." Phinney finds Bob on guard duty and tells him that Peggy is singing in his club. Mike asks Bob for $5,000 for Ma, but Bob says he doesn't have it. Bob fights and is knocked out. Bob is sorry that the Marines did not come to his opening, but Peggy says he deserved it. Among Chinese Bob sings "Night Over Shanghai" with Peggy. Bob fights a man for Peggy, and the man shoots Peggy. Then Bob carries her offstage. Phinney and Fowler show Bob the money they made. Bob tells them his club is closed. Bob blames the Marines for not paying Ma and gives Ma his club. Bob's discharge request is denied. Bob and Peggy kiss. Ma asks Bob to sing "The Song of the Marines."
This musical comedy reflects United States military commitment in Asia, where the Japanese were currently at war with China. The shy Bob lets success go to his head, causing his friendships to suffer.