Carol and Will travel for three and a half months. Carol manages to escape the Gopher Prairie malaise but eventually she longs for her son and they return. They leave Monterrey California on a beautiful sunny day and arrive in Gopher Prairie during a sleet storm. While they wait for a cab at the Haydock's, Juanita relates the latest gossip which is not very different from the gossip extant at their departure. When their cab comically wrecks against a tree, they elect to walk home. Kennicott observes all the small improvements about the town but Carol sees only its brute ugliness. She is happy to see Hugh but quickly despairs when her old dissatisfaction returns. Soon afterward Old Mrs. Perry dies of illness and Carol observes how the town turns its back on poor old Champ Perry who loses his job without a pension. She convinces Lyman Cass to give him an easy job as a night watchman. Major Raymond Wutherspoon returns from the war and for a time the town moons over him. Many people, including Will Kennicott, make a good deal of money on the rising wheat prices and land speculation and one speculator, James Blausser (who likes to be called Honest Jim) convinces the town to engage in a booster campaign. Everyone in town loves Honest Jim but Carol hates his obvious, crude mannerisms. At Jim's behest the town gears up to attract industry and government and puts in a White Way (a street of ornamental posts with clusters of high powered lights). Carol is disgusted by the town's new egomania. Kennicott is annoyed and angry that Carol does not share his enthusiasm for the boosting. One night an argument between Carol and Will erupts and Carol tells her husband that she is leaving until she can discover her work - that which will satisfy her; she doesn't know how long she will be gone and she intends to take Hugh. Kennicott protests that he needs her and she retorts: "You have a right to me if you can keep me. Can you?" He has no reply. After a month of arguing she departs with Hugh for Washington, D.C. to find war-work. When she leaves on the train she feels lonely and empty but free.
In Washington she finds office work at the Bureau of War Risk Management. She discovers that business women have freedom without losing domesticity and she loves the city's element of mystery. Through it all, however, she recognizes a streak of Main Street in the transplanted people from town's like Gopher Prairie who cleave together in the cities and shut out anything that does not remind them of home. She becomes friendly with a group of suffragettes. Though she never officially joins the group they adopt her and take her on their picnics and social gatherings. Most of her salary goes to a nurse for Hugh but she is happy in her small flat that she shares with other working girls whose open manners pleasantly shock her and knowledgeable conversation makes her wish to be younger. From these girls she learns of towns all over the country much worse than Gopher Prairie. Washington imbues Carol with poise and a comfortably impersonal attitude that allows her to rise above the pettiness of her former state of mind. She learns that laughter, not disgust or anger, is the best defense.
A year passes. She sees the Haydocks in town on business and is genuinely glad to see friends from Gopher Prairie, though she is equally glad to meet someone at the flat just in from Finland that night. Later, while speaking with a captain, she sees Percy Bresnahan. In the captain's opinion, Bresnahan is a nice enough fellow but a hopeless bother. She sees a rather bad motion-picture and is startled to see Erik Valborg (billed as Eric Valour) in a small and poorly acted part. After thirteen months Will comes for a visit that is both awkward and a relief. While sightseeing and going to restaurants and talking of inconsequential matters they cautiously negotiate their relationship. Carol finds that she is not ready to return to Gopher Prairie. He confesses that he misses her terribly but doesn't expect her to return until she is ready of her own accord. He begins to confess his adultery but she stops him and tells him to forget it. He asks her to take two weeks off of work to go to Charleston and Savannah with him - not a second honeymoon, he insists, but rather a second wooing. In Charleston she thinks she might return to him but he tells her to wait until she is ready. She finds a new respect for her husband and considers that his life, like hers, is something of a story. Sometime after Will returns to Gopher Prairie, Carol dines with a senior member of the suffragette movement. She asks the older woman's advice on whether she should return to her husband and the small town. The woman tells her that if she returns she should always question things and never expect change to come quickly. The woman tells her to think in terms of thousands of years. Carol believes she is ready to face Main Street. She realizes that she no longer hates the town - rather, she sympathizes with it and understands it and is ready to tolerate it. After five more precious months in Washington she returns to Gopher Prairie pregnant with her second child.
Comforted by Gopher Prairie's familiarity Carol is neither glad nor sorry to be back. It is simply her task, like going to work, to live there. She resolves to help Vida Sherwin and takes a shift at the rest room for the farmer's wives. She begins to wear spectacles in public. In general, the town accepts her and she accepts the town. In August she gives birth to a daughter. She realizes, with some satisfaction, that though she hasn't always fought the good fight she's maintained her faith despite Main Street.
Carol takes two important trips during this final section. The first trip is set in motion in order to get away from Gopher Prairie and the potential scandal, such as that which ruined Fern Mullins, resulting from her relationship with Erik. As the Kennicott's travel through the American West, Lewis cynically observes that the dynamic of their relationship has not changed: Carol is caught up in the beauty and wonderment of their surrounding and except for her son would be perfectly happy never seeing Gopher Prairie again. Will, on the other hand, spends most the trip seeking out people from other small towns and comparing notes. When he does engage in their surroundings it is only to itemize the dimensions of a mission or take stock of their progress. Nothing epitomizes the separation between the two more than their reaction to Gopher Prairie upon their
return. Will sees improvements and Carol sees only a sty. That this alienation is visible only to Carol only serves to convince her that she must escape Gopher Prairie to "discover her work". The time that she and Hugh spend in Washington, D.C. allows her the opportunity to gain what Lewis refers to as "poise" but what is really the ability to understand that her role in Gopher Prairie is not to overcome it but to exist as a member and thusly effect change from within. At the conclusion of her story, Carol is not content but she is not unhappy.