Producer Harry Sherman once again brought the "Hopalong Cassidy" unit to picturesque Lone Pine, CA, and the result was yet another tidy little sagebrush oater about the search for a missing gold mine. California Carlson (Andy Clyde) learns that his only remaining relative, Ben Pendleton (Britt Wood), may have struck gold just prior to being murdered in his isolated cabin. But when California and his two friends, Hoppy (William Boyd) and Lucky (Russell Hayden), arrive to learn more about the claim, they find the place already occupied by Trudy (Eleanor Stewart), Ben's niece. The old prospector's murderer, gambler Ace Gibson (Morris Ankrum), befriends Trudy and persuades her that the newcomers are outlaws out to jump the claim. Of course, the smooth-talking heavy has no idea who he is up against and is soundly beaten in a final confrontation with Hoppy.
by Hans J. Wollstein synopsis