 Colima County, Texas, has barred the entry of cattle from fever-ridden Sage County, where two unscrupulous schemers, Morhan (J.P.McGowan) and Conners (Tom London), have bought up thousands of head of the cattle, suffering from hoof-and-mouth disease (before the USDA decided to call it foot-and-mouth even though cattle don t have feet) for a song. Driving the cattle to a rail shipping point by crossing a corner of Colima Country, they are spotted and fired upon by Marjorie Miller (Dorothy Dix), daughter of Sheriff Ed Miller (Jack Rockwell.) The outlaws overcome, and are about to kidnap the girl, when Gene Autry (Gene Autry), traveling with the medicine show owned by "Professor" Parker (Earle Hodgins), arrives and rescues the girl. (Needed footnote: One of the musicians in the Autry troupe is western actor/musician Art Davis but he is billed in this film under his real name of Audrey Davis. We only bring this up because some uninformed source thinks the credited Audrey Davis is an actress.) Later, Morgan calls a cattleman s meeting to get the quarantine lifted, and has a fake veterinarian (Harrison Greene) falsely testify that the fever is not contagious.But Gene and his musicians distracts the crowd, and gives Gene a chance to show up the fake. Morgan tells Gene to get out of town by five o clock, but Gene tosses a bottle of medicine to Conners and shoots it out of his hand. The deadline is mentioned no more. Sheriff Miller and a deputy are shot from ambush. Gene takes the wounded Miller to a ranch and orders all to keep it a secret that Miller is alive. Morgan, figuring the sheriff is dead, orders a new election, hoping to put one of his own men in office and lift the quarantine butGene is pressed to run by the locals and wins. The desperate Morgan and Conners decide to run the cattle through anyway. Gene, Frog (Smiley Burnette) and Gene s hands, including the non-actress Audrey Davis/Art Davis, ain t having none of that.