This chapter opens with a description of the Valley of Ashes, a desolate area of land between West Egg and New York City. In this industrial wasteland, through which the commuter train must pass, everything is covered with dust, smoke, and ashes. But above this gray, ashen land, there is a sign of hope - a huge advertisement painted on the side of a building. The ad shows the large, blue eyes of Dr. T.J. Eckelberg, oculist, looking out from an enormous pair of yellow glasses. The eyes, which are just beginning to fade in color, appear to be brooding over the gray wasteland below them.

This bleak setting is the appropriate home of Tom Buchanan's mistress, Myrtle Wilson. One Sunday afternoon in July, when Nick and Tom are riding into the city, the train stops at a drawbridge in the Valley of Ashes. While the train is at a standstill, Tom grabs Nick's elbow, forces him from the car, and says, I want you to meet my girl. They walk through several blocks of nothingness until they enter Wilson's Garage and Repair Shop. George Wilson, like the building and its surroundings, is covered in ash and spiritless in nature. In contrast to him, his wife Myrtle, in her mid thirties, is very sensuous, with an air of vitality about her even though she is faintly stout and unattractive. Tom taunts George with a promise to sell him his automobile and tells Myrtle to get on the next train. She is always ready to escape from the Valley of Ashes, and gladly obliges Tom. She discreetly sits in the next car, away from her lover. In New York, however, the three of them get in a cab together and head towards the apartment that Tom rents for her.

On the way to the apartment, Myrtle, possessed with purchasing things, insists upon stopping to buy a puppy being offered by a gray old man on the street corner. Tom pays the man for the dog and comments that it's a bitch, words that Myrtle ironically could not say even though she is a mistress herself. Nick tries to leave the cab to take a pastoral stroll through the park in the soft warmth of the bright afternoon, but Tom insists that Nick come up to the bleak apartment, which is a small, crowded one bedroom flat on the top floor. (Symbolically, Nick is torn between the order of his pastoral Midwest and the chaos and flash of New York.)

The crowded apartment is soon packed with additional guests -- Myrtle's sister Catherine (described in ashen terms) and the McKees, who are neighbors from downstairs. A party of sorts ensues with much drinking and inane conversation. Myrtle, who has changed her clothes for the third time in a matter of hours, also changes her personality from the earlier vitality found in the garage to one of false pretension, with exaggerated laughter and phony gestures. She loudly complains to everyone present about her husband George and says, I married him because I thought he was a gentleman...I thought he knew something about breeding. She next goes on to tell how she was horrified to discover that he had borrowed the suit he had worn to their wedding. She then tells Nick about meeting Tom on the train for the first time, being attracted by his clothing, and convincing herself to go off with him since you can't live forever.

By nine o'clock, Mr. McKee has fallen asleep, and Nick quickly goes over and wipes from his face a spot of dried lather that has bothered him all afternoon. Myrtle, by this time, is orally making a list of all the things she has planned to buy: a massage, a permanent wave, a collar for the puppy, a special kind of ash tray, and a wreath with a black silk bow that will last all summer for her mother's grave. She then states, I got to write down a list so I won't forget all the things I got to do. In the midst of it all, people seem to disappear and reappear, to make plans to go somewhere and then lose each other. Nick admits that he has had too much to drink and that everything appears vague and shadowy, as if Myrtle has brought the Valley of Ashes with her.

Nick describes himself at the party as being within and without, simultaneously enchanted and repelled by the inexhaustible variety of life. The spell of the party, however, is broken around midnight when Tom and Myrtle argue loudly over her talking about Daisy. Tom insists that she not even mention his wife's name. When Myrtle taunts him by shouting, Daisy! Daisy!...I'll say it whenever I want to, Tom answers by striking her face and breaking her nose. Nick's sense of moral order is repulsed by the violence, and he leaves in an alcoholic stupor, finally catching the 4:00 a.m. train back to West Egg.