After drifting into the goldrush town of Skull Creek, Montana, Dr. Joseph "Doc" Frail buys a cabin on the hill above town from a penniless prospector. Soon after, Rune, a young wanderer, tries to steal a gold nugget from a sluice box and is pursued by a bloodthirsty mob, guns ablaze. Hearing the injured Rune's cries for help, Doc rescues the boy and bandages his wound. In payment for his services, Doc demands that Rune become his bond servant, threatening to expose him as a thief if he refuses. Doc then sets up practice, and although he exhibits compassion for his patients, he can be imperious and severe when dealing with others, prompting Tom Flaunce, the town storekeeper and an old acquaintance, to comment that "Doc carries his soul in his doctor's bag." When Doc is assailed by George Grubb, a raving drunk who accuses him of being the devil, Doc, an expert marksman, drives Grubb off at gunpoint. While at the saloon one evening, Doc strikes a gambler who questions him about burning down a house in Illinois. One day, a stagecoach is attacked by a band of robbers, causing the horses to bolt and the carriage to careen over the side of a cliff. With his dying breath, the driver reveals that a woman passenger, the sole survivor, is trapped in the coach. Frenchy Plante, a lecherous prospector, Rune and Flaunce head a search party for the woman. While camped around the fire for the night, Flaunce informs Rune that Frail is a name the Doc assumed because he felt that it described the state of mankind. Flaunce then relates the story of a doctor named Temple, who torched his grand house on the river after discovering the dead bodies of a man and a woman inside. The next day, Frenchy finds the missing woman, whom he dubs "Lost Lady." After they carry the unconscious woman to a shack in a nearby meadow, Doc examines her and declares that she is suffering from temporary blindness. He arranges for her to be transported to Flaunce's abandoned cabin, which is situated across from his own, and Rune volunteers to care for her. Three days later, the woman regains consciousness, although she remains blind. After identifying herself as Elizabeth Mahler, she learns that her father was killed in the robbery. When Elizabeth tells Doc about emigrating from Switzerland to the "wonderous" America, Doc cautions her that she will find no glory in the wretched town of Skull Creek. Soon after, Flaunce's wife Edna, a mean-spirited, priggish woman, drives to the cabin to determine if Elizabeth is "decent," and is turned away by Doc. That night, after Doc leaves to play cards at the saloon, Frenchy sneaks into the cabin. When Elizabeth senses his presence, he claims that he has come for his canteen. As Frenchy is about to sexually attack the blind woman, Doc appears and orders him to leave. Later, at the saloon, Doc thrashes Frenchy and threatens to kill him if he ever returns to the cabin, and Frenchy vows revenge. As the days pass, Rune accuses Doc of trying to control people and objects to his isolation of Elizabeth. One day, Elizabeth is on the verge of recovering her eyesight when she lapses back into hysterical blindness. Doc inspires her to see again, but when she embraces him, he coldly informs her that she must leave the next day. Doc then gives Rune his freedom and presents him with a horse. The following morning, Rune and Elizabeth ride into town and Elizabeth shows Flaunce a brooch, an old family heirloom, and asks to use it as collateral for a grubstake. When Flaunce reports Elizabeth's request to Doc, Doc gives him the money to lend to her. Entering into partnership with Frenchy, Elizabeth and Rune establish the "Lucky Lady" mine. A month passes, and Doc continues to funnel money into the mine, unbeknown to Elizabeth. While out delivering a baby one day, Doc stops to say hello to Elizabeth. Jealous of Doc's intrusion, Frenchy manhandles Elizabeth and she decides to move into town. When Elizabeth comes to the store for another advance, Edna cruelly informs her that the brooch is worthless and accuses her of prostitution. Furious, Elizabeth accuses Doc of trying to play with people's lives and he admits that the rumor about the grand house on the river is true and that the man and woman were his wife and brother. In the midst of a violent rainstorm one day, a giant tree near the Lucky Lady is uprooted, revealing a pit filled with gold nuggets. To celebrate the strike, Frenchy plies the townsmen with liquor. While Elizabeth repairs to Doc's cabin with her sack of gold, the drunken revelers below turn mean and set the town on fire. Barging into Doc's cabin, Frenchy hurls Elizabeth onto the bed and assaults her. Doc returns to find the town in flames, then hurries to his cabin and throws Frenchy down the stairs. When Frenchy pulls his gun, Doc shoots him and then kicks his lifeless body over the hillside. Grubb seizes the opportunity to incite the frenzied crowd to lynch Doc, and as they place a noose around his neck, Elizabeth, bruised, hobbles down the hill and offers her gold in exchange for Doc's life. The greedy mob stampedes to the mine, leaving Doc behind. After Rune removes the noose from his neck, Doc bends down and caresses Elizabeth's face and they embrace.