An evil ranch foreman tries to provoke a range war by playing two cattlemen against each other while helping a gang to rustle the cattle. Each cattleman ends uo blaming the other for missing cattle.
When the notorious bandit El Toro saves Hoppy from a bog, the newly deputized Sherriff Cassidy agrees to rescue the aging outlaw's young grandson.
Hopalong Cassidy and the Bar 20 boys aim to put an end to a power-hungry cattle rustler's dreams of building his own personal Xanadu in the West.
Hoppy has to bust up a gang of outlaws with the help of his sidekicks Shanghai and Johnny. As usual, he walks through the fusillade unscathed.
An evil gang is involved in both cattle rustling and the robbing of stagecoaches. Hoppy must stop them without help from the sheriff who turns out be a major outlaw himself.
Ranch owner Sally Jordan is engaged in a fence war with rancher Big John Trumbull. Hoppy and Johnny, along with trusty sidekick Windy, side with Sally Jordan.