'Black' Brown, a notorious road agent on the run from the law, stumbles on the body of John Lawrence, an honest prospector during the early years of the California Gold Rush, riddled with Indian arrows. Brown takes the dead man's clothes and papers and is able to pass himself off as a good citizen in 1850's Calaveras County. When Lawrence's sister dies, her daughter spends the little money she has to journey to California and live with her uncle. Arriving at the isolated cabin, she realizes he is an impostor, but his threats intimidate her into silence. Lacking money and protection, she immediately becomes vulnerable to the advances of the largely all-male population, and so must acknowledge Brown publicly as her uncle in order to continue to receive food, shelter, and his protection. Over time, this understanding of mutual convenience turns to affection, and he pledges to reform. When former members of his gang continue their dishonest ways, however, the now rehabilitated Brown falls under the suspicion of the local vigilante committee.