Royal Canadian Mountie Renfrew (Newill) tangles with gangster Cardigan (Stone), with the help of his young sidekick Kelly (O'Brien) in the second of the "Renfrew Of The Mounties" series. Ann (Blaine) had witnessed a bank robbery, so the robbers kidnapped and took her with them, locking her in a trailer with the loot. The trailer's hitch loosens, and it plunges into the lake. Sergeant Refrew rescues Ann out of the water, but she gives him a false name, afraid he will send her back to the authorities, who want her as a material witness to the robbery. Renfrew and Ann are captured by the gang of robbers, headed by gangster Cardigan, who wants to know what Ann did with the money. It's up to Constable Kelly to concoct a plan to save the day.
