Jan, the hunter, is in love with Marie, a French-Canadian girl. The same charmer has captivated Otto, the driver of the Wilderness Mail, a vengeful and selfish individual. Mane has a half-sister, Joan, a decided contrast to her, a sweet lovable girl not ordinarily bold or aggressive, but when aroused firm to a finish. She resents the way her sister meets these two suitors, the one following the other, as quite unworthy of a modest woman and hotly tells her so. First comes good-natured Jan, who presents Marie with the pelt of a beautiful red-fox. He is hardly out of sight in the woods when the mail driver comes, and she greets him even more effusively with kisses. He also gives her a present. Joan, outraged by her demonstration, speaks to Marie sharply, and Otto tries to conciliate her, but she in shame and mortification, runs to the woods. Otto soon drives his dog team along down the snowy trail and meets Joan, roughly parleys with her and tries to kiss her. She struggles and screams. A little distance away in the woods, Jan is talking with some woodsmen. He hears Joan's cries and rushes to the rescue. Otto is so sorely worsted, he can hardly stand alone, but is helped to his feet by the two woodsmen as Jan takes the girl away. The news of Jan's victory has reached the settlement, and the next morning he is given a commission to get a letter through to Fort Hope before the Wilderness Mail reaches there, carrying advices that would rob a good man of his fortune. With a fresh dog team, and a big reward in view, Jan forges ahead, and overtakes the phlegmatic Otto idly dull from his beating. In crossing a frozen lake, Jan falls through. Otto passes on with a deaf ear to all his calls for help, sure that his enemy will perish miserably. Happily, Jan's dogs are more humane, and tugging at their lines move him to safety on firm ice. An outlaw lies in wait to rob the Wilderness Mail. He is about to shoot the advancing man when he discovers his mistake, for Jan is again ahead. He lets Jan pass by, but when Otto comes upon the scene, he kills him. Then he climbs a tree over the scene of the murder, and by dropping into the tracks of Jan, cunningly conceals his own trail. Soon two Northwest mounted police put in an appearance, find the body of Otto, and observing the trail of Jan, conclude he is the murderer. Jan, unconscious of the crime that has been committed, rushes on his way, delivers the packet entrusted to him, so that the good news gets there first, justice is done and the man's property is saved. He then recuperates after his long journey, takes the back trail home when he is met by the mounted police, who arrest him, accusing him of the murder of Otto. He denies the charge strenuously and rankling under the injustice of it, makes a stout resistance, but is eventually overcome and carried back to Fort Hope, bound as a prisoner. The news soon reaches the settlement and the lone cabin of the two sisters, Marie and Joan. The former immediately writes a bitter note to Jan, upbraiding him wrathfully as the murderer of the only man she ever loved. Joan is so firmly convinced of the innocence of Jan that she concludes to go to him, making a long journey over the lonely trail to Fort Hope. When she is admitted to the prisoner, he describes his trip in detail, how Otto left him to drown, and later tried to shoot him, but that he had gone on ahead unmindful of it. This reassures Joan more than ever that Jan is innocent. Thereupon she determines an investigation upon her own account, returns to the scene of the crime and, by studying the situation carefully, observes how the murderer climbed the tree, traversed the long branch, and dropped into the trail of the man ahead. She then follows the side trail which leads to the lonely cabin of the outlaw. Joan draws her revolver, enters the cabin and finds the outlaw befuddled in liquor, mussing over the plundered mail. She tries to arrest him, but drunk as he is, he makes resistance and endeavors to grapple with her. She shoots him in the arm, then binds his hands behind him and drives him before her back to the headquarters of the police where she delivers him as the real murderer. Hers was the most unusual and daring deed, and was highly commended by the authorities. Jan is released upon the confession of the outlaw, and the last scene shows Jan and Joan entering their own cabin in the dimming light, presumably after the service in the little church in the clearing where their wedding had been celebrated.