In 1881 and George Kracha, a Slovak peasant from the Austro-Hungarian Empire, boards a ship in Germany to immigrate to America. Aboard the ship, he meets a voluptuous woman named Zuska Mihula and foolishly spends what little money he has on an alcohol-fueled birthday party for her. As a result, when Kracha arrives in New York, he lacks the money to buy a train ticket and thus sets out for Pennsylvania on foot. There, he meets up with his sister, Francka, and her husband, Andrej, who secures Kracha a job working for the railroads. Kracha also befriends a fellow Slovak immigrant named Joe Dubik. After a year, Kracha’s wife, Elena, joins him in White Haven. She is sickly and depressed and has an unsightly goiter in her neck. Elena’s poor health repels Kracha, and treats her coldly as a result. She nonetheless bears him three daughters: Mary, Alice, and Anna. Dubik marries Dorta, and they soon move to Braddock, Pennsylvania, where Dubik begins working in the blast furnaces. Andrej and Francka then make a similar move to Homestead, Pennsylvania, where Andrej gets a job in the steel mill. With his friends gone, Kracha follows suit and moves to Homestead.
When the Krachas arrive in Homestead, Andrej pays his Irish foreman three dollars to give Kracha a job in the steel mill. He and Andrej soon visit Dubik and Dorta in Braddock. They drink whiskey and discuss work in the mils. It is hard, dirty, backbreaking, relentless, and dangerous physical labor. Meanwhile, Mike Dobrejcak, an intelligent, literate Slovak immigrant, comes to Braddock, boards with Dubik and Dorta, and works in the mill. In 1892, skilled workers go on strike in Homestead. The company, under magnate Andrew Carnegie and union-buster Henry Clay Frick, respond by smashing the union. Kracha moves his family to Braddock’s poor First Ward and obtains a job in its blast furnace. Not long afterwards, an explosion in the furnace kills Dubik. After Dubik’s death, Kracha leaves the steel mill and buys a butcher shop. At first, he prospers, and invests in some potentially profitable land plots on the advice of Joe Perovsky, a saloon owner and real estate speculator. Kracha only wants to make money, and has no desire to assimilate into American culture or vote.
One day, Zuska walks in to Kracha’s shop, having moved to Braddock after her husband’s death. Kracha immediately begins lusting after her again, and the two begin an affair. Francka and Dorta berate Kracha for his adultery, while Elena grows sicker. Word of the affair spreads, costing Kracha several customers, and his land investment fails to pan out. Elena dies, and Mary finds a job working for the wealthy Dexter Family. Kracha marries Zuska, but the funeral costs exhaust his savings, and he loses the butcher shop. He gets drunk and beats Zuska, who leaves him. He later discovers that she has been stealing his money. Destitute, Kracha returns to work in the steel mill.
It is now 1900, and 25-year-old Mike Dobrejcak works hard to assimilate into American culture. He learns to speak and read English, studies U.S. history, and resents that his status as a “Hunky” keeps him from getting a better job. He soon falls in love with Mary Kracha and the two begin to date. Mike aspires to own a large, furnished house like that of the Dexters and other “Americans.” Mike and Mary get married and have their first child, John Joseph. They move into a larger house and Mary gives birth to a daughter, Pauline. Mike continues to resent working the same mill job for little pay, and Mary takes in boarders to help make ends meet. The extra work is tiring, but the added income allows them to pay their debts. Anna starts work for the Dexters, and Alice elopes.
The next year, Mary has their third child, Mikie, and John starts school. At the mill, Mike must work the grueling 24-hour shift. The experience numbs his body and soul. Mary is also working long hours cooking, cleaning, washing, and sewing for the children and boarders. One summer day, she faints, and Dr. Kralik tells her she must rest and give up the boarders or risk getting sicker. She reluctantly lets the boarders go, and the loss of income weighs heavily on the family, especially after they have their fourth child, Agnes. Mike continues to worry about his low pay when the mill cuts his shift. He laments to Mary that no matter how hard he works, he can never get ahead, and feels that he will never be anything more than a “Hunky.” As the midterm elections approach, Mike wants to vote for the socialist candidate, Eugene Debs, but the company bosses warn him and the other steelworkers that voting anything but the Republican Party will cost them their jobs. He votes for Debs anyways, but the company does not find out. After the election, Mike gets drunk at Joe Wold’s saloon with Steve Bodnar, and pours out his anger over the lack of a steelworker union, the company’s intimidation, and the fact that hard work gets him nowhere. He expresses pride in his work creating steel, but feels that the owners of the steel industry treat him like an expendable piece of machinery instead of a human being with hopes and dreams.
At the start of the New Year, Kracha fractures his arm while loading scrap. He visits Braddock during the christening of Anna’s second baby. Mary bakes a cake for John’s eleventh birthday, and she suggests that Kracha stay the night. After the birthday party, Mary and Mike discuss the injury that Alice’s husband, Frank Kovel, sustained in the mill, and his plans to move the family to Michigan and invest in a farm. Kracha remarks that Mary looks healthier since giving up her boarders. As the evening ends, Kracha goes out drinking while Mike goes to work the night turn at the mill. After Kracha returns to Mary’s house around midnight, he hears a knock on the door and answers from the second floor window. A man outside informs Kracha that Mike has fatally burned in an accident at the steel mill. Cursing his fate at having to break the horrible news to Mary, Kracha goes into her bedroom and tells her that Mike is dead.
Mary receives $1,300 from the company as compensation for Mike’s death, yet she has no time to grieve. She cannot put the household work off and must get the children ready for school the next morning. Unable to bear being in the rooms where she and Mike lived, Mary moves to a two-room dwelling in a house full of boarders and children. In a town where men frequently die in the steel mill, she soon learns that people have finite sympathy for women thrust into widowhood. Unable to work full time due to the children, Mary takes jobs sewing, washing, and cleaning part-time at a dentist’s office. Meanwhile, John collects scrap for pennies, hunts for coal, and sells newspapers on the street corner to bring money to the family. Desperate to make ends meet, Mary convinces a grumpy and reluctant Kracha to move in with her, thereby contributing boarding money. John and Pauline begin school in Munhall, and John gets a part-time job delivering wallpaper. When summer arrives, he gets a job in a glass factory, providing needed extra income. On Christmas Eve, the police arrest Kracha for drunken public conduct, and Mary and John find him jailed and penniless.
When spring arrives, John wants to drop out of school to work full time, but is too young. He convinces the school principal’s secretary to write him a new birth identification and forges the date to list his age as sixteen. The scheme works and soon John finds work as an apprentice armature winder in the North Braddock steel mill. Shortly after New Year’s, Mary falls ill and is bedridden for long stretches. Dr. Kralik says that both she and Pauline have contracted Spanish Influenza and recommends that they check into a sanitarium. Mary gives her $500 insurance policy over to Anna and wills her $750 policy to Agnes. She then has a jeweler carve John’s initials onto her engagement ring and gives to him before taking Pauline and Mikie and moving into the sanitarium. John moves in with Alice, and Kracha moves to Homestead to live with Francka. Soon there is a strike at the steel mill and John learns about unions from his uncle Frank. The strike drives John to get construction work in Donora. Back in Braddock, striking workers battle against the company and its allies, the state police.
John visits his siblings at Christmas time. They exchange presents, and John tells Mikie to start calling him “Dobie,” a nickname his coworkers in the electric shop have given him. After over a year spent in the sanitarium, Mary’s condition worsens. She begins dreaming about the life she should have: about her boys as grown men and her girls as beautiful young women. She wonders how her life came to take such awful turns, and even convinces herself that she will wake up one day to find Mike alive and by her side. She soon dies peacefully in her sleep. Pauline dies a year after her mother. Following Mary’s death, the sanitarium discharges Agnes and Mikie. The former goes to live with Anna, the latter stays with Dobie at Alice’s house.
One day, Dobie casually overhears to the mutterings of his General Superintendent, Mr. Flack, at the steel mill. John’s brother, Mikie, is now working as an apprentice machinist in the mill with his cousin, Chuck. After finishing his apprenticeship, Dobie decides to move to Detroit. There, he works in the Chrysler plant and in a wheel factory. After five years in Detroit, Dobie moves back to Braddock and lives in Perovksy’s hotel just as the Great Depression sets in. The steel company cuts wages and reduces hours. The poor economic conditions affect everyone save for the very rich. Dobie earns extra money by hooking up unauthorized power lines to skim services from the utility companies. Around this time, he meets and falls in love with Julie, who is to be maid of honor at Agnes’ upcoming wedding. Dobie and Julie begin dating, while Dobie’s aunt Anna informs him that the upcoming elections will be devastating for the incumbent Republican Party. In Homestead, Kracha runs out of money, and Francka attempts to hasten his mortal demise by keeping him drunk. Her plot fails and Kracha eventually moves in with Dobie. Julie and Dobie get engaged and bring Kracha to move in with them since his pension will provide needed income.
The government takes over relief duties and the steel mills re-open, although they do not run a full capacity. The passage of the National Industrial Recovery Act grants workers the right to collectively bargain through their chosen representatives, but the company skirts the law by creating Employee Representation Plans (ERP), a form of company union led by steel bosses. The ERP infuriates Dobie and other workers, and it spurs the American Federation of Labor (AFL) to send organizers into the steel towns in an attempt to build legitimate unions. Dobie becomes active in the Braddock lodge and soon the men elect him secretary of the union. He gives speeches and organizes to get steelworkers to join the union. Julie is proud of his labor work and tells him he is the best man for the job. Soon, Dobie’s immediate bosses in the mill, Mr. Todd and Flack, hear of his organizing activities and threaten his job, but Dobie does not stop his union work, including trying to bypass Walsh, the useless organizer from Pittsburgh.
At home, Dobie is astonished when his grandfather tells him that steelworkers in Braddock were once unionized. The ERP continues to stymie legitimate organizing, and workers grow increasingly agitated that their union is unrecognized. The union prepares for a strike, but cancel at the last minute when the AFL forms a Labor Board instead. In the fall, Kracha suffers a stroke but survives. Desperate to revive the union, Dobie and Steve Gralji hatch a plan to take over the ERP from within. The plan works and they are elected union representatives. Their efforts receive a huge boost when labor leader John Lewis forms the Committee for Industrial Organization (CIO) to organize the steel workers. The CIO sends men to organize in the mill towns. Meanwhile, Kracha suffers another stroke and dies, and Julie becomes pregnant.
The CIO calls on Dobie to testify in Washington, DC, against the company’s anti-labor activity, to which he readily agrees despite Todd’s threat to fire him. In Washington, Dobie believes the hearing should be held in a mill town and overseen by a jury of the thousands of ordinary people who gave their lives to the steel industry. When he returns to Braddock, Flack accuses Dobie of lying about the company, but Dobie stands up to him and finds that his job is secure. Early the next spring, the steel company capitulates and signs a contract with the CIO, freeing the steel industry after a fifty-year struggle. Following the union’s victory, Dobie imagines the fight ahead, in which every human being must enjoy the right to live life as they see fit, and to be defined by, but not constrained by, their place of birth in the world.