Bids submitted to win the U.S. Mail contract for their stagecoach lines are entered by both singing cowboy Bill Harkins and the Banton brothers, Roy and Bart. During a stagecoach race to determine who is awarded the contract, Roy, fueled by his greed as well as his desire for Bill's lady friend, resorts to sabotaging his rival's rig in order to win. Bill, having an idea who is behind a recent rash of stagecoach robberies, devises a plan to catch the highwaymen but not before he is himself arrested for robbery and murder, having been seen committing the crime by impartial eye witnesses.