After an elusive and unidentified outlaw known as "The Sidewinder" burns down the property of rancher Tex McCloud (Sterling Hayden), Tex accuses the cavalry of ineptness -- and Lt. Tom Blaine (Forrest Tucker) bets a year's salary that they will capture the Sidewinder first. Saloon owner Carolina (Arleen Whelan) offers to cover Tex's side of the wager, but asks in exchange that he help her collect a debt from mine owner Lucky Lee (Victor Jory) and his pretty fiancée, Nora Logan (Barbara Rush).