Sal arrives at his old friend Remi Boncoeur's place in Mill City, a shack in a housing project outside of San Francisco, and moves in with Remi and Remi's girlfriend Lee Ann. Remi is delighted to see Sal and has a lot of ideas for him. Sal writes a screenplay that Remi says he'll sell in Los Angeles, and he starts working where Remi works, as a nightguard at a barracks for overseas construction workers. Predictably, Sal is an ineffective security guard. One night, he goes to try to quiet the men, but ends up drinking with them and hanging the flag upside down the next morning without noticing. The other cops are hard-core--one of them likes to tell of his good days at Alcatraz--and are suspicious of Sal and Remi. On the nights when Sal and Remi work together, they steal groceries from the barracks cafeteria. Money is tight, but Remi is always full of risky ideas, and they work together. One day they, with Lee Ann, row out to a rusty freighter and spend an afternoon there picnicking and sunbathing. Remi is disappointed that the ship has been stripped by previous thieves, and Sal dreams of the ship's more glorious days. Sal finds Lee Ann sexy, but keeps his promise to Remi to stay away from her.
Sal also goes to San Francisco some days, trying and failing to seduce women. He is starting to get restless again. Relations in the shack are getting frayed. The screenplay idea failed, Lee Ann and Remi are constantly fighting, money is tight and Remi loses the last of it at the racetrack. Remi asks the two of them for just one favor: his stepfather is visiting and he wants to him out, and for Lee Ann and Sal to at least act like his girlfriend and best friend. Sal is impressed by Remi's gentlemanliness, but still blows Remi's plans by arriving to the dinner drunk and late. On top of that, Roland Major shows up drunk and rude. This is the end of Sal's friendship with Remi. Sal decides to go back East, via Los Angeles and Texas. On his last day in Mill City, he climbs to the top of a nearby canyon, looks over San Francisco and the Pacific Ocean, and reflects about being at the end of the continent.
Sal walks through Oakland and hitchhikes to Bakersfield. Unable to get more rides, he gets on a bus for the remaining stretch to L.A., where he sees a small, pretty Mexican girl. She is sitting across from him on the bus, and he finally screws up the courage to talk to her: Terry. They tell each other their respective stories, and decide to stay together in L.A. After they arrive and are eating breakfast, Sal starts to feel suspicious that Terry is a hustler. After they get to their hotel room, he feels nervous and acts strange. Terry gets suspicious too and becomes convinced that Sal is a pimp. Sal pleads with her and then gets angry. Finally, they both trust each other, and they make love and fall asleep together.
Sal's stint in Mill City is a stint in the "real word," a stationary, working, poor world. Sal enjoys the closely-packed shack community, but he can't handle daily working and fighting for long. He is still the responsible Sal: he bails Remi out of a bad situation at one point, and sends most of his earnings to his aunt. But he doesn't thrive in this situation. Eventually, he cannot resist drinking and ruining Remi's dinner with his stepfather--the "one last favor" Remi asked of him. He also tells how he occasionally went to bars, and when approached by a gay man, would pull his security gun on the man. Sal openly admits that he never understood why he did that--he knew many gay men already and didn't have problems with them--but attributes his action to "the loneliness of San Francisco" and the fact of having a gun and therefore wanting to show it to people.
At the end of the same paragraph, he says that he has to leave San Francisco or else he will go crazy. Sal's constant movement, viewed in this light, becomes not just whimsy, but a necessary tactic for survival. Standing on a canyon rim on his last day in Mill City, looking over San Francisco and toward the ocean, he reflects that he is at one end of the continent, with nowhere to go but back East. In this moment, he thinks of the East as "brown and holy," and California as white and vacuous, empty. It is not so much the places, as his ideas of them, which drive Sal from one to the other. He craves and thrives on movement and novelty.
Stylistically, the sentences and paragraphs are shorter in the Mill City section, more narrative and less descriptive. Sal is looking toward L.A.--now L.A., not San Francisco, not Denver, is the "ragged promised land." He describes himself and Terry in L.A., after they have made love, as two tired angels. Terry is described in realistic detail. For the first time, a new Western acquaintance of Sal's is first an individual, less an epitome of a place or caricature of a region (though there are still aspects of this: her skin Sal describes as "brown as grapes"--which she and her family pick for their livelihood). In all of the disappointment and distrust, as evidenced by Sal and Terry's episode of mutual suspicion, they still attain human closeness, and Sal was desperate for it. Through shifts in descriptive pace and detail, Kerouac shows us his narrator maturing, growing in perceptiveness.