Jane and her brother live in the north woods. Jim, a ne'er-do-well, is in love with Jane and she reciprocates his affections. Jane's brother, Tom is a member of the Northwestern Mounted Police, and while on a furlough, notes the growing change in Jane. One day he surprises her while in Jim's arms. Tom recognizes Jim as a card shark and drunkard and warns his sister of the man. Jane, lover like, refuses to believe any ill of her sweetheart. Tom goes back to his patrol and one day receives a summons to arrest a murderer. Jim has engaged in a card game, is caught cheating, and kills his accuser. He escapes and goes to the girl's home. While he is trying to get her to help him get away her brother Tom comes on the scene. He tells Jane of the man's record and she tells him she knows it and that he must help Jim escape Tom thinks of his oath and refuses. He and Jim engage in a fight. Jane gets Tom's gun and is going to hold him while Jim escapes. The murderer gets a knife and is about to attack Tom when the call of her blood rises within Jane and she shoots her former lover thus saving the life of her own blood brother.