A sedan used in smuggling narcotics speeds north from Tiajuana, Mexico. In it are gangsters Mooney and Tony Rocco, and Rocco's son, Johnny. . A California motorcycle cop overtakes it. Mooney suddenly brakes the sedan, the officer smashes into it and is killed. Johnny is shocked by the murder and Mooney cautions Rocco to keep the kid's mouth shut. Later at school, Johnny's teacher, Lois Mayfield, noticing something is troubling Johnny, calls on his father and awakens in Rocco an awareness of the world Johnny is being exposed to. The narcotic smuggling syndicate head, Gordon Lane, fearful that Johnny will tell all he knows, orders Mooney to trail the boy. To escape Mooney, Johnny runs into a church where he is befriended by Father Regen. Police Inspector Garron, meanwhile visits Lois, who was seen emerging from Rocco's apartment. She explains her mission there, and Garron, now suspecting Rocco, confronts him with the assertion that the gang will stop at nothing if they think the boy will talk. Rocco insists he knows nothing of the murder of the motorcycle cop, but he also realizes he now must protect his son's life. Rocco provides Father Regen with money to care for Johnny and asks Lois to let Johnny live with her. Then he returns to his apartment to await whatever the gang may deal him. But he hasn't counted on his son's loyalty. Johnny runs back home and enters just as as his father is shot by Mooney. Inspector Garron closes in for Mooney's arrest. Meanwhile, Johnny discloses it was Mooney, not his father, responsible for the motorcycle officer's death. Johnny, taken under care by Rather Regen and Lois, hopes his father recovers from his wounds and may enjoy a respectable future.