Ben Halpen sets up his barber's shop at the turn of the century in Sevillinois and watches the town grow around him. Thinking it is for the best, he tries to shield his wife Nellie from the worries of the world. She finally rebels while he is away at war and takes a fateful trip to Chicago. This turns out to be the first of a number of critical family crises for Ben.

In 1945, the citizens of Sevillinois, Illinois, prepare to celebrate the town's fiftieth anniversary. A reporter seeking a story on Senator Lloyd Slocum, who was the town's first mayor, is told to question Ben Halper, the town's first barber. As the reporter talks with Ben, the elderly man remembers his first night in Sevillinois: Ben is on a train with his new bride Nellie, who believes that they will honeymoon in Chicago. Nellie is severely disappointed when they instead disembark in the tiny town of Sevillinois, where Ben has invested in a barbershop. Although Ben tries to persuade Nellie that there are advantages to establishing a business in a growing town, her tears prompt him to lie that he is renting the shop, while actually he has purchased it. Ben promises to take Nellie to Chicago when they have more money, and the couple soon settle into the apartment behind the shop. They become friends with the families of hardware store owner Ed Jordan; livery stableman George Oliphant; general store proprieter Sam Eichenbogen; and Slocum, the town's mayor and only attorney. On their wedding anniversary, Ben surprises Nellie with a new home, but is nonplussed when she reacts with anger. Nellie explains that she still wants to go to Chicago, and Ben again lies, telling her that he is only renting the house. Ben joins the town band and fire department, and soon expands the barber shop by hiring "Trooper" Robert Waverly Fairless, a black ex-cavalry man seeking a job as a bootblack. Soon after, Ben Halper, Jr. is the fourteenth child born in Sevillinois, and Ben's contentment continues until one night, at a party, Nellie allows the roguish Jordan to kiss her. Jordan's wife Bessie and Ben discover the brief flirtation but quickly cover it up. Ben then prepares to leave for military service during the Spanish-American war and asks banker Burdge to serve as the executor of his estate. Ben cautions Burdge not to let Nellie know that he owns both the shop and their home, and later, bids farewell to Nellie. Nellie, who regrets the impulsive kiss, reveals that she is expecting their second child. Several months later, Nellie has given birth to daughter Adeline, while Ben serves as a barber in a Georgia training camp. One afternoon, Jordan offers to take Nellie on a vacation to Chicago, but she declines. Nellie changes her mind, however, when Burdge reveals the extent of Ben's ownership of town property. Infuriated, Nellie leaves Benny and Adeline in the care of Trooper and leaves with Jordan. Soon after, Ben receives a telegram notifying him of Nellie's death in a train wreck, and upon his arrival home, is heartbroken to learn of her betrayal. Ben's friends gently rouse him from his drunken depression and promise him that there will be no gossip about Nellie. Although he gradually becomes bitter and cynical, Ben carries on with the shop and rearing his young children, with Trooper's help. Several years later, Ben is about to propose to a townswoman but is interrupted by the sound of the fire bell. It is Ben's barbershop that is on fire, and after the building is burned down, Ben's friends help him to raise the money to build a new, larger shop. The gentle Trooper continues to urge Ben to forgive Nellie as the years go by, and soon, Adeline is in high school and Benny has graduated. Rather than going to medical school, as Ben prefers, Benny wants to become a dancer, and has perfected an act with Eadie, Jordan's daughter. When Ben angrily declares that he will hear no more talk of vaudeville, Benny and Eadie run away together to Chicago, and Ben does not hear from them for a year. Eventually, Ben receives a telegram from Benny summoning him to Chicago, and there he watches with pride as Benny and Eadie perform their headlining act. Ben still responds gruffly, however, when Benny informs him that he and Eadie are married, and that he has joined the Army to serve in World War I. After Ben and Eadie return to Sevillinois, Eadie confides in Ben that he will soon become a grandfather, and Ben softens and asks her to move in with him and Adeline. Later, after the birth of Eadie's daughter, Nellie Jordan Halper, Benny is reported missing in action, and the Halpers await news. Benny is found, wounded but alive, and many months later, returns home with a severe limp. Benny then joins Ben at the barber shop, but, hoping for a more prosperous life, falls in with a Chicago gang run by racketeer Kava. Ben is outraged to learn that Benny is selling "protection insurance," and approaches Kava, asking him to leave Benny alone. Kava arrives at Ben's barbershop the next morning and states that Benny is returning with him to Chicago, and so Ben, desperate to save his son, does not tell Kava when Benny calls to say that a rival gang is on its way. The gangsters spray the shop with machine guns just as Benny enters, and both he and Kava are killed. Grief-stricken, Ben finds comfort in his granddaughter, and spends the following years helping to care for her. Ben, who has fallen asleep during his reminiscences, is awakened by Nellie, who looks exactly like her grandmother, and he then joins his friends in the celebratory parade.