In Apache, Arizona, Patrick Livingston, the owner of the Diamond A Ranch, receives a telegram informing him that his wife Mary and daughter Beatrice are arriving on the three o'clock train. Soon after Mary joins her husband, the couple are killed in an Indian attack engineered by Francis Livingston, Patrick's stepbrother. Francis is then awarded custody of Beatrice, over the protests of Jim Raymond, foreman of the Diamond A, who promised Mary that he would take care of the girl. Soon after, a note written by Patrick blaming Francis for his death is brought to the attention of Pat Garrett, the county sheriff. Before Garrett is able to act, however, Francis is killed by Dick Tracey, a notorious outlaw, and Beatrice disappears without a trace. Years later, Edna Sherwood, whose father was recently killed by the Tracey gang, moves from the small family ranch to a friend's home in Phoenix. Looking for employment, Edna answers a newspaper ad for a schoolteacher at the Diamond A Ranch. Jim, who is still running the ranch, falls in love with the new teacher and they wed. When Tracey tries to ambush him in the hills one day, Jim kills the outlaw and later moves to the city with Edna where Jim becomes a successful businessman. One day, a man named Charles Lewis visits Jim at his office and introduces himself as someone who knew Edna as a child. After Jim invites him home, Lewis reveals the Edna is really Beatrice. As a child, she was found by a prospector in Arizona who placed her in the orphanage where Sherwood adopted her.
