Hoppy's friend Dennis owns a rich gold mine. Frazier who owns the adjoining mine and wants the Dennis mine, has Dennis killed. Hoppy steps in to take over running the Dennis mine and learns Frazier's men sneak into and work the Dennis mine at night. Hoppy captures one of Frazier's men only to be captured in return by Frazier and left to die in a burning building.
William Boyd
as Hopalong Cassidy
George 'Gabby' Hayes
as Windy Halliday
Russell Hayden
as Lucky Jenkins
Gwen Gaze
as Ann Dennis
William Duncan
as Buck Peters
Pat J. O'Brien
as Frazier
Paul Sutton
as Slade
John Beach
as Denny Dennis
Joe De Stefani
as Perkins
Walter Long
as Pierce
Bruce Mitchell
as Ross
Chuck Baldra
as Miner
