Gene Autry is the foreman of a ranch mortgaged to the hilt with a fast approaching deadline to build a dam. When the owner dies and leaves the Rancho Grande to his three madcap grandchildren, Gene must straighten out the rebellious young folks and make them work to pay off the debt and foil the villains. It will take brawn, brains, and of course a few songs, to uncover the secret plot to take over Rancho Grande.