In River's End, Alberta, Canada, John Keith is tried for the murder of Roger Cass and sentenced to hang, although he swears his innocence. John escapes and heads into Canada's frozen north, planning to return when he finds out who framed him. Sergeant Derry Conniston, a new Royal Canadian Mountie, is sent to find John and tracks him on a dog sled through the snow for several months. Derry breaks his leg as he nears John's hideout, and John rescues him. They become friends and Derry realizes John is no killer. John believes he was framed by Cass's gold mine partner, Norman Talbot, who testified against John at the trial. When John shaves off his beard, Derry is struck by their resemblance and, aware that he is dying, urges John to take his place. John puts on Derry's Mountie uniform just as two Mounties sent to find Derry enter the cabin. As Derry dies, John, as Derry, tells the Mounties he gave Keith his word he would investigate his case. John returns to River's End and asks his friend, Andy Dijon, to help him prove Talbot's guilt. John then returns to Derry's cabin and finds a woman waiting for him. Afraid she is Derry's wife, John is relieved to discover she is Derry's sister Linda, who has not seen her brother in six years. Meanwhile, Linda falls for Talbot, against John's admonition. John and Andy then investigate Talbot's friend, Frank Crandall, sending him to jail to make him talk. Linda and Talbot decide to marry, and John is forced to tell that her Talbot is a murderer and confesses his true identity. Linda runs out believing John killed her brother and reports to the Mounties, who arrest John. While Talbot and Linda escape in a wagon to elope, Andy forces a confession from Crandall, who knows Talbot is guilty, and John is released. When the Mounties set out in pursuit of Talbot and Linda, John takes an alternate route alone and catches up with the couple. Talbot and John struggle, and Talbot nearly falls off a cliff, but John saves him so he can face his trial. Talbot is sentenced to hang, and the Mounties give Linda a posthumous award for Derry. Linda and John then wave goodbye to Andy, who has finally agreed to marry his aggressive admirer, Cheeta.