Gene Autry and sidekick Frog Millhouse depart Madison Square Garden and NYC heading west for home in their car and a horse trailer carrying Gene's horse, Champion. They discover that Ronnie Willoughby, a young boy just off the boat from school in England, has hitched a ride, thinking that Gene and Frog were sent by his father to meet him. Ronnie thinks his father is a big rancher in the west and doesn't know that his father, Alfred Willoughby, is serving time in San Quentin prison because of a frame-up by the officials of a packing company. To keep the father from testifying against them, the packing company officials, Carter, Jenkins and Martin, have arranged for the boy to be kidnapped. Along the way a runaway bride, Joyce Halloway, and her young sister Patsy join the troupe.