The Three Mesquiteers convince a group of settlers to exchange their present property for some which, unbeknownst to our good guys, is going to be worthless. They are captured before they can warn the ranchers.
Marshal Wyatt Earp kills a couple of men of the Clanton-gang in a fight. In revenge Clanton's thugs kill the marshal's brother. Thus, Wyatt Earp starts to chase the killers together with his friend Doc Holliday.