Jack and Dolly, his sister, live together in the west. On Jack's birthday, Dolly presents him with a peculiar ring. The brother and sister attend a masquerade ball that evening, each dressed in the other's clothes. Dolly, being taken for a man, meets Big Bill, a new ranchman, and he offers her a cigar, which she tries to smoke. Jack sees her in distress, and coming to her rescue, is introduced as the sister. The next morning Jack leaves to look over his stock. While riding through the sage brush, he takes a shot at a rabbit and the bullet lands near the spot where a cattle rustler is plying his unlawful trade. The cattle rustler and Jack meet. The former believes that Jack tried to kill him and a fight follows. Jack is killed.