 The Rancho Castanares, near the Pueblo Santa Barbara and stretching from the mountains to the sea,is threatned by a decree of the American government requiring Spanish land-grant owners to register their holdings by June 15th, or see them revert to public domain.Scheming Don Pablo Gonzales(Francis Ford)advises his wealthy friend Don Jose Castanares(Lafe McKee)to defy the government decree, as he wishes to grab the Rancho Castanares for himself, and it is obvious that his lazy son,Luiz(Donald Reed),will not obtain the property through marriage to Jose s daughter Dolores(Ruth Hall), who dreams of meeting a dashing storybook hero.Knowing an entrance cue when he heard one, in rides U.S.Army Captain John Holmes(John Wayne)on his (credited) horse Duke, sent by the government to convince the land-owners to protect their property by registration.John, guided through the countryside by a fast-talking gent of shady fortune, Felipe Guadalupe Constacio Delgado Santa Cruz de la Verranca(Luis Alberni)---Felipe to those who can t spell Spanish names---wins the trust of Don Jose and the wrath of the steaming and still-scheming Gonzales.John wins an unlikely ally when he prevents the arrest by U.S.Army troops of outlaw Jake Morgan(Slim Whitaker as Charles Whittaker), who promises to leave the Rancho Castanares alone and provide help anytime John might need it.Which turns out to be soon.Don Jose, on his way to meet John and register his land, is kidnapped by Gonzales  henchmen, and when Dolores goes searching for her father and arrives at the Gonzales ranch, she is held hostage and forced to consent to marriage to Don Luis to save her father.But among the guests at the hastily-assembled wedding are John and Jake in the company of Luis jilted lover, Anita(Nina Quatero)and her outraged "aunt" who is Felipe in disguise(or"drag" for those who prefer the term.)Greatly outnumbered by Gonzales  hired henchies, John, Jake and Felipe fight with swords and ceramic projectiles(as might be expected from a man in drag)while Duke(the Miracle Horse)leads Jake s gang to the rescue.A remake of 1928 s "The Canyon of Adventure" and features a few scenes where, courtesy of stock footage, John and Duke magically turn into Ken Maynard and Tarzan.Warners reissued this in 1939 and the other westerns Wayne made for producer Leon Schlesinger, with revised artwork(ugly) and updated tagline identifying Wayne as the "hero of "Stagecoach" and "Allegheny Uprising", but Duke,the Miracle Horse kept his accustomed billing.