Before he was killed by Mark Foster's men, Bud Lawton willed part ownership in his ranch to Hoppy and his two pals. When the three arrive they find a fake posing as Lawton. When they expose the imposter, Foster gets the Sheriff to jail them for Lawton's murder.

William Boyd
as Hopalong Cassidy

Andy Clyde
as California Carlson

Jimmy Rogers
as Jimmy Rogers

Douglass Dumbrille
as Mark Foster

Tom Seidel
as Bud Lawton / Kit Moyer

Claudia Drake
as Faith Lawton

Robert Mitchum
as Rip Austin

Glenn Strange
as Sonora

Pierce Lyden
as Lefty

Roy Barcroft
as Sheriff