The discovery of gold in California in 1848 brings a tide of gold seekers to the area, disrupting the lives of the Guerrero family who have owned nearby Rancho Chico for generations. Among these are Dermod D'Arcy, in partners with a jailer, Bejabbers. At a fiesta where horse races are traditionally run, a stranger notices Dermod's exceptionally fast horse, Pathfinder, and urges him to enter the horse in the race. It becomes a three-horse race, with Don José Guerrero betting his ranch that his horse will win. When Pathfinder wins, Dermod takes the ranch as his share of the winnings and gives it to Don José's daughter, Josephita, with whom he had fallen in love earlier, when he met her. Dermod and Bejabbers leave to search for gold, and the town grows rich as more and more gold is amassed. Meanwhile, a bandit chief, Cannon, met Josephita's brother, Romauldo, and forced him to join the gang, which planned to loot the town of its gold before Wells and Fargo shipped it east. As two of the gang set a fire to draw most of the townsmen to put it out, Dermod overhears them discussing the plan and warns the townsmen to stay put. The gang is captured, tried and sentenced to be hung. Dermod is convinced Romauldo is innocent and ponders how to save him.