A western outlaw finds his lost son on the other side of the law and helps him without telling him their relationship.
In 1879 Arizona boxer Jeffrey Burton (Dennis O'Keefe) and his manager Eight Ball Harrigan (Guy Kibbee) ride a stage coach and are held up by Trigger Bill (Wallace Beery) and Ben (Joseph Calleia). Bill clubs Jeffrey with a pistol and takes his watch. In town Jeffrey meets Loretta Douglas (Virginia Bruce). When Jeffrey demands his watch back, Bill sees a photo of Jeffrey's mother and realizes he is his son. Bill shoots a man for insulting him and makes Ben swear not to reveal that Jeffrey is his son. Loretta learns that the Grants are leaving because Bill took their herd. Jeffrey asks Loretta to marry. Her father Jackson Douglas (Lewis Stone) says there is no law enforcement. Loretta asks him to teach Jeffrey law. Jeffrey tells Sheriff Barney (Charley Grapewin) he will collect taxes. Bill divides the money for the cattle, taking half. Jeffrey shows Bill his tax bill of $780. Bill gives him the money and goes with him. Bill asks Jeffrey about his father. They make Jake pay, and Bill shoots another man to get his money. Jeffrey hits Bill, who does not fight back. An ambush by Vulch McCreedy (Guinn Williams) fails, and Jeffrey turns in the taxes. At Vulch's funeral Blackjack McCreedy (Bruce Cabot) asks who killed him. Bill says he'll take care of it.
Bill asks lawyer Jackson Douglas how he can leave $3,000 for Jeffrey's college education. Loretta persuades Jeffrey to go, and they kiss good-bye. Blackjack thanks Bill for the massacre. Loco found silver, and Bill wants to own the town. People speak against Bill's corruption; but Judge Douglas signs an order and is given money. Sheriff Blackjack McCreedy goes to enforce it. Jeffrey and Eight Ball return, and Jeffrey tells Loretta he is a federal marshal. Douglas buys Eight Ball a drink and drops his bank-book. Blackjack learns that Jeffrey killed his brother but kills Eight Ball by mistake. Jeffrey pulls his gun as marshal and faces off with Blackjack; but Bill intervenes and gets Blackjack to submit to arrest.
Men ask Jeffrey to appoint them vigilantes; but he prosecutes Blackjack for murdering Eight Ball. Blackjack claims Eight Ball resisted arrest, but the jury convicts him. However, Judge Douglas sentences Blackjack to only one year or a $500 fine. Jeffrey demands that Douglas resign and shows him his bank-book. Loretta asks her father to explain, but he collapses. Douglas says that Bill is Jeffrey's father. Bill pulls guns and tells Blackjack and others not to tell Jeffrey. Bill apologizes to Jeffrey. A gun battle begins to stop Jeffrey after Blackjack shoots Douglas; Ben and others are killed. Dying Douglas asks Jeffrey to take care of Loretta. Jeffrey thanks Bill and offers him amnesty for his gun; but Bill goes after Blackjack and kills him. In the final scene Bill comes back to see Jeffrey wed Loretta before he is arrested.
This combination of western violence and parental sentimentality offers typical Beery entertainment. Progress is symbolized by the law-abiding efforts of the younger generation represented by Jeffrey and Loretta.