In December 1929, Nick Carraway, a World War I veteran, is undergoing treatment at a psychiatric hospital. He tells his doctor about Jay Gatsby, the most hopeful man he ever met. The doctor suggests he write down his thoughts since writing is Nick’s passion. Nick begins cataloging the events to his doctor.
Seven years earlier, in the summer of 1922, Nick moved from the Midwest to New York after abandoning writing. He rents a small groundskeeper’s cottage in the North Shore village of West Egg, next to the mansion of Gatsby, a mysterious business magnate who often hosts extravagant parties. Nick has dinner with his beautiful but oppressed cousin Daisy Buchanan and her athletic, domineering husband, Tom. Daisy plays matchmaker between Nick and another guest, Jordan Baker, a famous golfer whom Nick finds attractive. When Nick returns home, he sees Gatsby standing by the harbor, reaching toward a green light coming from the Buchanan dock.
Jordan tells Nick that Tom has a mistress who lives in the “Valley of Ashes”, an industrial dumping site between West Egg and the City. Tom takes Nick there, stopping at a garage owned by Tom’s mistress, Myrtle Wilson, and her husband George.
Nick receives an invitation to one of Gatsby’s parties. Upon arrival, Nick learns he is the only one who received an invitation and none of the guests have ever met Gatsby. Nick encounters Jordan, and both meet Gatsby. Gatsby later takes Nick to Manhattan for lunch. On the way, Gatsby tells Nick he is an Oxford graduate and war hero from a wealthy Midwestern family. They go to a speakeasy, where Gatsby introduces Nick to his business partner, Meyer Wolfsheim.
Jordan tells Nick how US Army Captain Gatsby started a relationship with Daisy in 1917, just before the US entered the war, and is still in love with her; he throws parties hoping that Daisy might attend. Gatsby asks Nick to invite Daisy to tea. After an awkward reunion, Gatsby and Daisy begin an affair. Gatsby is dismayed when Daisy wants to run away with him, preferring that she get a proper divorce. He asks Nick and Jordan to accompany him to the Buchanan home, where he and Daisy plan to tell Tom that Daisy is leaving him. During the luncheon, Tom becomes suspicious of Gatsby and Daisy, but Daisy stops Gatsby from revealing anything to Tom and suggests they all go to the Plaza Hotel. Tom drives Nick and Jordan in Gatsby’s car while Gatsby drives Daisy in Tom’s car. Tom stops for gas at George’s garage, where George tells him that he and Myrtle are moving and that he suspects Myrtle is unfaithful.
At the Plaza, Gatsby tells Tom of his affair with Daisy. Tom accuses Gatsby of having never attended Oxford and having made his fortune through bootlegging with mobsters. Daisy says she loves Gatsby but cannot bring herself to say she never loved Tom. Eventually, both Gatsby and Daisy leave. After fighting with George over her infidelity, Myrtle runs into the street and is fatally struck by Gatsby’s car after mistaking it for Tom’s. After learning about Myrtle’s death, Tom tells George that the car belongs to Gatsby and that he suspects Gatsby was Myrtle’s lover. Nick deduces Daisy was driving when the accident happened. Nick overhears Daisy accepting Tom’s promise to take care of everything, but he does not tell Gatsby. Gatsby admits to Nick that he was born penniless; his real name is James Gatz, and he had asked Daisy to wait for him until he had made something of himself after the war; instead, she married Tom, “America’s Wealthiest Bachelor”, just seven months after the war ended. He did, however attend Oxford, albeit for a brief 5 months on a special program for officers after the Armstice.
The next day, Gatsby hears the phone ringing and thinks it is Daisy. Before he can answer it, he is shot and killed by a vengeful George, who then commits suicide. Nick is the only person other than reporters, to attend Gatsby’s funeral, as Daisy and Tom are leaving New York. The media paints Gatsby as Myrtle’s lover and killer. This false, negative image of Gatsby’s life and death infuriates Nick and from the top of the stairs at Gatsby’s mansion he yells at the reporters and kicks them out of the house. Disgusted with both the city and its inhabitants, Nick leaves after taking a final walk through Gatsby’s deserted mansion and reflecting on Gatsby’s ability to hope. In the sanatorium, Nick finishes typing his memoir and titles it The Great Gatsby.