Captain John Allister of the United States Cavalry discovers Deputy Sheriff “Red” Greeley and four companions in the act of attacking a group of Indians. Through a ruse, John proves that their accusation that the Indians were rustling horses was merely an excuse to steal the gold that the Indians were transporting to El Rio. He arrests the men and turns them over to Sheriff Bill Ryan. Lee Burgess, foreman of the ranch owned by Don Fernandez, is secretly allied with Greeley. John and Sheriff Ryan travel to the Fernandez ranch to purchase some horses for the army. Burgess tries to sell them inferior horses for a high price, but John discovers the trick. At the ranch, they meet Fernandez’ daughter Dolores, who much prefers John to Burgess, despite the latter’s attempt to pressure her to marry him. The prisoners escape from jail and Greeley is suspected of helping them. Fearing an Indian uprising, John declares martial law. He joins the Indians on their next gold transporting trip, disguised as a cowboy, and prevents any theft. On the evening of Dolores’ birthday fiesta, Burgess plans to rob the stagecoach bringing the army payroll into town. Lieutenant Wilbur Allister, John’s brother, is guarding the payroll. He has been transferred West to reform his drinking habit under John’s supervision. Wilbur is wounded in the holdup and taken to Don Fernandez’ ranch to recuperate. During his convalescence, he falls in love with Dolores, not realizing that she is the woman his brother loves. Always the gentleman, John steps aside, but makes Wilbur promise that he will be worthy of Dolores. Under Burgess’ influence, however, Wilbur starts drinking and gambling again and then is himself accused of robbing the stage and murdering a man. Using evidence provided by the Indians, John proves that Greeley and Burgess are guilty of the crime and rides off with the army to capture them, leaving Wilbur behind with Dolores. More on Wikipedia
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