One of three films made in the six-announced "Morton of the Mounted' series: Sergeant Bruce Morton (John Preston (I)'), in charge of the Three Rivers Post of the Royal Northwest Mounted Police is informed by White Feather ('Chief Whire Feather'), an Indian fur-trapper, that for many months, most of the local fur trappers have been systematically robbed, but refuses to name the robbers, fearing for his life. Morton, his horse Dynamite (Dynamite the Horse), his dog Captain (Captain King of Dogs), and a RCMP corporal, Jimmy Downs (Jimmy Aubrey), set out to apprehend the culprits. After rescuing Yvonne Travis (June Love) from the treacherous waters of Horse Shoe Rapids, Morton learns that her father is a fur trader indebted to Monty Mordant (Tom London), who runs the trading post, and Mordant is using her father's debt to force Yvonne to marry him.