Writer Nick Carraway pilots his boat across the harbor to his cousin Daisy and her husband Tom’s mansion in East Egg. While there, he learns Tom and Daisy's marriage is troubled and Tom is having an affair with a woman in New York. Nick lives in a small cottage in West Egg, next to a mysterious tycoon named Gatsby, a former Oxford student and decorated World War I veteran, who regularly throws extravagant parties at his home.
Tom takes Nick to meet his mistress, Myrtle, who is married to George Wilson, an automotive mechanic. George needs to purchase a vehicle from Tom, but Tom is only there to draw Myrtle to his city apartment, where he hits her in the face when she taunts him with Daisy's name.
Back on Long Island, Daisy wants to set Nick up with her friend, Jordan, a professional golfer. When Nick and Jordan attend a party at Gatsby's home, Nick is invited for a private meeting with Gatsby, who asks him to lunch the following day.
At lunch, Nick meets Gatsby's business partner, a Jewish gangster and gambler named Meyer Wolfsheim, who rigged the 1919 World Series. The following day, Jordan appears at Nick's work and requests he invite Daisy to his house so that Gatsby can meet with her. Gatsby surprises Daisy at lunch, and it is revealed that Gatsby and Daisy were once lovers, though she would not marry him because he was poor.
Daisy and Gatsby have an affair, which soon becomes obvious. While Tom and Daisy entertain Gatsby, Jordan, and Nick at their home, Daisy, on a hot summer day, proposes they go into the city as a diversion. At the Plaza Hotel, Gatsby and Daisy reveal their affair and Gatsby wants Daisy to admit she never loved Tom. She is unable to and drives off in Gatsby's car.
During the drive home, Daisy hits Myrtle when Myrtle runs into the street. Believing that it was Gatsby who killed Myrtle, since Tom tells or implies this to him, George later goes to Gatsby's mansion and fatally shoots him as he relaxes in the swimming pool, then commits suicide.
Nick holds a funeral for Gatsby where he meets Gatsby's father and learns Gatsby's original name is "Gatz". No one else attends the funeral. Afterward, Daisy and Tom continue with their lives as though nothing occurred. Nick breaks up with Jordan and moves back west, frustrated with eastern ways, and lamenting Gatsby's inability to escape his past.
