 Lifting the plot straight from Tim McCoy s 1936 "Ghost Patrol" this Renfrew version finds the planes carrying gold from the Yukon mine mysteriously disappear, and when Sergeant Renfrew (James Newill) and Constable Kelly (Dave O Brien) find the wreckage there is no clue as to what happened. They follow the next plane shipment in another plane but when radio announcer Dinwiddle (Dewey Robinson) learns of the flight, he broadcasts the plans by means of a coded bedtime story to a gang headed by Morgan (William Pawley), who prepare to bring down the plane with a mystery ray that wrecks the plane s magneto. Speavy (Dwight Frye), who invented the ray, is jealous when Professor Lewis (Joseph Stefani), a scientist innocently working for the gang, is hired to increase the ray s range. The two Mounties, trailing the gold plane, see it crash, but are unable to locate the wreckage of the gold. Madeleine Lewis (Louise Stanley) joins her father and Renfrew sees her enter the gang s hideout. He enters and Speavy tries to kill him with the ray, but he escapes. The gang moves their headquarters but Renfrew plans to fly a gold shipment himself to force their hand. Morgan, in another plane, tries to force Renfrew into the deadly beam but Professor Lewis, having learned the truth about the gang, turns the ray on Morgan s plane.