The Pony Express days are coming to an end, with riders John Blair (John Wayne) and his friend Larry Adams (Lane Chandler), both about 75 pounds too heavy for the original job description, out of a job. They pay Cal Drake (Douglas Cosgrove) of Buchanan City a big price for the Crescent City line and equipment, and arrive there to find it is a ghost mining town and has only two residents: eccentric, self-proclaimed Mayor "Rocky" O'Brien (Lew Kelly) and Dr. William Forsythe (Sam Flint). With the arrival from back east of Barbara Forsythe (Phyllis Fraser), the doctor's daughter and Ginger Rogers lookalike, O'Brien happily changes the blackboard population sign from two to five. John determines to get even and operate the line anyway, after vacating a resident skunk from the stagecoach. On his first run into Buchanan City John learns of a coach race to be staged (fastest team to win a $25,000 government mail contract) and he signs up. A telegraph crew, drinking unknowingly of a poisoned ...