A traveling performer arrives at a remote South American port town where the head of an air freight service must risk his pilots' lives to earn a major contract.
Young scout Breck Coleman leads a wagon train along the dangerous trail to Oregon as he tries to get the affection of the beautiful pioneer Ruth Cameron and plans his revenge on the harsh scoundrels who murdered a friend of his in the past.
The Three Mesquiteers convince a group of settlers to exchange their present property for some which, unbeknownst to our goodguys, is going to be worthless. They are captured before they can warn the ranchers.