In this chapter, Nick Carraway recounts an important day when he accompanies Tom Buchanan, his cousin Daisy's wealthy and domineering husband, to New York City. The chapter begins by describing the desolate area known as the Valley of Ashes, a stark contrast to the opulence of West Egg and East Egg. This wasteland symbolizes the moral and social decay resulting from the uninhibited pursuit of wealth, a recurring theme in the novel.

As they travel, Tom's character is further revealed through his arrogance and disdain for those he considers beneath him. The Valley of Ashes is home to Myrtle Wilson, Tom's mistress, who is married to George Wilson, the owner of a rundown garage. Tom brings Nick to meet Myrtle, and the two men take a train to the city, where Tom's affair becomes more evident.

Upon arrival at Myrtle's apartment in the city, Nick is struck by the stark differences between the lives of the characters he encounters. Myrtle, who is desperate to escape her mundane life, is portrayed as vivacious yet shallow, embodying the empty pursuit of social status. The apartment is lavishly furnished, showcasing Tom's wealth and their illicit relationship's superficiality.

The gathering in the apartment becomes increasingly chaotic as Myrtle invites some friends over, including her sister, Catherine. The atmosphere is filled with debauchery and excess, highlighting the moral decay of the era. During this party, Tom's brutish nature comes to the forefront when he violently strikes Myrtle after she taunts him by mentioning Daisy's name. This act of violence underscores the power dynamics at play in their relationship, as Tom exhibits control through aggression.

Nick's discomfort grows throughout the evening, as he observes the superficiality and emptiness of the interactions around him. The chapter concludes with Nick leaving the chaotic scene, feeling a sense of disillusionment with the world he has entered, further emphasizing the themes of corruption and the hollowness of the American Dream. Nick's experiences in this chapter serve to deepen his understanding of the complexities of the characters surrounding him and set the stage for the unfolding drama of the novel.