A gang of outlaws takes over El Dorado, a ghost town, just before gold is rediscovered there. With the boom comes easy money for Gils Brandon and his henchmen. Meanwhile, vigilantes, seeking to curb the lawlessness of the town, offers the job of Marshal to Steve Rawlins. On the day that Gil's fiancée, Ellen Randall, arrives in town, Gil is shot when he makes an attack on the new Marshal. Discovered in a dying condition by his twin brother, Buck Brandon, Gil regrets his outlaw past and asks Buck to make El Dorado a decent place. Steve learns of the relationship and enlists the aid of Buck in cleaning up the town.