Based on Harry Segall's play, a movie star, who plays detectives, thinks he can solve a real crime better than the police.
In Hollywood movie star William Martin (Jack Oakie) gets a death threat. Publicity agent Mary Strand (Ann Sothern) asks William to apologize to the police. William goes late to the set and invites quarreling Ralph Waring (Bradley Page) and Doris Dunne (Joan Woodbury) to a club. William rehearses. At the club William uses the speech Mary gave him to wipe gum from his shoe. A waiter and photographer slap each other. Ralph won't let Larry Frank (Alan Bruce) dance with Doris, and Larry knocks Ralph down. In his speech William makes fun of the police, but Mary turns out the lights to stop him. Mary asks the police to act in William's movie. A man with an umbrella shoots at William. Mary goes with William to see Professor Horman (Eduardo Ciannelli), who shows her punishment methods. William shows Horman the threatening note.
On location William helps police Lt. Garrison (Edgar Kennedy) get ready with a toupé. Larry arrives drunk and is fired by the director Gibbons (Paul Guilfoyle). During the car chase Horman shoots at William and kills his driver Ralph. Horman puts the gun in the hand of unconscious Larry, who is arrested by Lt. Garrison. William says in the movies the obvious suspect is never guilty, but he is reprimanded by Mary. William tells his servant Warts (Willie Best) he knows who did it. Horman comes in, and William says he will find the murderer. William calls together all who were there, and a witness listens to them. Horman tries to leave, but Garrison makes him speak. The witness says it was William. In his car William finds a note. A cop gives him a ticket, preventing Horman from shooting. Mary tells William he needs a bodyguard. William puts on a beard and boards a tour bus, as does Horman. William gets off at his house. A reporter questions him, and Horman shoots at him.
Mary is ordered to muzzle William. As he drives, she signals to police. William is arrested, and Mary leaves him in jail. Garrison tells Mary that the note was written by a foreigner. Horman bails William out of jail, and Warts tells Mary about that. She sees Horman's writing and suspects him. Horman pulls a gun on William, who gets the gun. Horman has William shoot six bullets, and they fight. Mary and the police arrive as Warts operates the punishment devices. Finally Horman is arrested, and William kisses Mary.
This comedy satirizes detective movies and Hollywood stars who get caught up in their own glamour, confusing their roles with reality.