In 1870s San Francisco, as Ada Stritch's bank faces a run, newspaperman Johnny Sanderson goes to ask millionaire Rip MacCool if he will save the bank. Even though the state's economy depends on the bank's survival, Rip refuses to help. Soon Flutey Johnson, an old associate of Rip, also comes begging for his help, as does Ada, who needs three million dollars. Rip deals a hand of cards and suggests that Ada, who loathes him, bet her bank against the money. Before calling the bet, Johnny suggests that they learn more about Rip. Ada then recalls their first meeting, more than fifteen years before: Ada, a widow, runs a modest hotel at which Rip and his Serbian friend Shocker rent a room. Rip confides to Shocker that he wants to buy the hotel and learns from a prominent financier that $3,000 would be a fair price. When Ada suggests to Rip that she wants to sell the hotel and return East, he invites her to his room and, while making love to her, offers $3,000 in cash and $1,000 of stock in the Mona Lisa mine, somewhat less than she had wanted. She agrees, but her affection for him turns to hate when he callously tricks her out of $300 of the hotel's income and she learns that the stock is worthless. Ada concludes her story, and Johnny begins: After Johnny badly loses a boxing match, Rip defends his honor against a man who wrongfully accuses him of throwing the fight. Rip then offers Johnny, who is an aspiring writer, a job as night manager of the hotel. Some time later, Rip loses all of his cash in the stock market and becomes even more determined to become rich. Two years later, Rip has turned the hotel into a luxurious place and made $8,000, but confides to the sympathetic Shocker that he fears he will never rise high enough. One day, Rip hears that the Mona Lisa stock is about to skyrocket and secretly buys enough shares to net him a $250,000 profit. Although he is happy that Ada, too, has become rich with the stock, she does not believe him. The next day, Rip saves the wealthy and influential Alexander Tomson from an embarrassing encounter with his wife while Tomson is romancing the beautiful Lily Douvane. In gratitude, Tomson gives Rip some inside stock tips and Rip becomes a millionaire. Flutey then picks up the story: Within five years, Rip is one of the city's most important men and employs Lily as a singer in a fancy restaurant managed by Flutey. Sensing that Johnny, who nows runs a newspaper, is attracted to the gold-digging Lily, Rip proposes to her, confessing that he is not romantically interested in her. She agrees, but on their honeymoon, admits that she does not even like him. Despite the circumstances of the marriage, she gives birth to a baby boy, whom Rip names after Johnny. Neither parent shows interest in the boy, who is lovingly cared for by Zoe Carnot, a French nanny whom Rip has hired on Shocker's recommendation. Rip is soon caught in a compromising situation by Lily, who demands a million dollars for an annulment and custody of the child. During the next year, Johnny sees a lot of the boy and Zoe, with whom he has fallen in love. He proposes, but she tells him that both little Johnny and Rip need her. Rip then proposes, suggesting that it will quiet the gossips and help the child. Rip does not return or appreciate Zoe's love, but is jealous of Johnny's devotion to her and the child. He begins to drink and carouse too much, causing his business to fail. Zoe, whose only concern is for Rip, borrows money from Shocker to help Rip regain his fortune. At a party, she learns that the Mona Lisa mine, part of the Comstock load, may have a new, rich vein of ore. She gets money to buy more stock by mortgaging the house at Ada's bank while Rip and Shocker secretly investigate the quality of the mine. Despite Ada's intervention, Rip is able to confirm that the mine is rich and makes a fortune when the stock climbs. Rip basks in his regained fortune, and, though grateful to Zoe, seems uninterested when he learns that she is pregnant. On the day that Zoe gives birth, though, he realizes his feelings and is shattered when both she and their baby daughter die. Johnny then explains that after Zoe's death, Rip had no interest in anything but the stock exhange. After Rip briefly leaves the room, Shocker explains what happened to Rip when he was sixteen: On a wagon train west, Rip's parents die of cholera and Rip is unable to raise the money necessary to give them a proper funeral. The hard-headed mortician refuses to let him work for the money, saying that in the West, having "the jack" is the only thing that is important. Rip then goes to work as a miner and meets Shocker, who later helps him dig his parents' graves. With only Shocker and shares in the supposedly worthless Mona Lisa mine, Rip then determines to earn his fortune. As Shocker finishes his story, Rip comes in and asks Ada to call her hand. Rip then looks at his last card and tells her the money will be at her bank in the morning. Ada leaves, suspicious that Rip did, indeed, have the cards needed to win, but he merely walks upstairs, smiling.