Sal prepares for another jaunt West with Dean and friends; he wants to go along for the ride, and hopes to have an affair with Marylou in San Francisco. Before they leave, the group stays at Carlo's place for awhile. Carlo tries to ask them all serious questions about what they are doing (and what they have done to Camille, Galatea and Lucille), but gets nothing but giggles for answers. Sal comes in every day and watches the spectacle.
One day, sitting in a bar, a blushing Dean tells Sal he wants Sal to make love to Marylou while Dean watches. Sal knows that it's because Dean wants to see how Marylou would be with another man. He agrees, but when all three of them are lying on the bed together, he can't go through with it. Finally, with Carlo irritated, his apartment a mess, and Dean and Marylou banged up from fighting with each other, the group starts on their trip.
They pass through Washington, D.C., on the day of Harry Truman's second-term inauguration. Ed Dunkel starts driving, and against their instructions, drives recklessly and they are caught and taken in to a police station. The police are suspicious of them, but can't do anything more than charge a $25 fine--leaving them only $15.00 to cross the country. They start picking up hitchhikers to try to get some gas money. Their first hitchhiker is a scraggly Jewish wanderer, who claims to find the Torah in the wilderness, their second a sad boy who lies that he has an aunt who can give them some money.
They pass through South Carolina, Georgia and Florida. Dean steals gas when a station attendant isn't paying attention, and tells them his life story: jumping freight trains with his drunk father, losing his virginity at nine years old. They arrive in drowsy Louisiana and go to Bull Lee's house, a dilapidated house on swampy land outside of town. Jane Lee greets them, high on benzedrine as always. Eccentric writer-junkie Bull Lee greets Sal courteously; Bull and Jane's two kids are running around the yard. Sal describes Bull: a "Kansas minister," a collector of experiences who has worked as an exterminator and traveled around the world, and now spends most of his time experimenting with his drug habit. He is the teacher of their group; Sal and Carlo have both learned from him.
Bull asks them questions about themselves that they can't answer--as usual--and gives them drugs; he considers Dean a madman. Then they go out in New Orleans, and Bull deliberately takes them to the dullest bars to prove that bars aren't what they used to be. It's a foggy, ghostly night. They stay up at Bull's house, everyone with their own project, and Sal goes out, wanting to sit by the Mississippi River. Unfortunately, he has to content himself with looking at the river through a fence.
They spend the next morning immersed in Bull's weird life: picking nails out of a wormy piece of wood, throwing knives at a target, hearing stories of Morocco, and fighting with his neighbors, and then go to a racetrack, where Bull loses money. Back in Bull's backyard, they compete by showing each other athletic tricks: Dean is the fastest. Later, in New Orleans, they go to the railyards and hop on and off freight trains, Dean showing off his brakeman skills.