The main character in the book is a Lithuanian man called Jurgis Rudkus, an immigrant to the United States trying to make ends meet. The book begins describing the wedding feast beginning at four o'clock after the marriage in Chicago of Jurgis to a fifteen year old Lithuanian girl named Ona Lukoszaite whom he had known from his Lithuanian days. The second chapter goes back to when Jurgis and Ona were in Lithuania before they married and Jurgis's courtship of her, the death of her father, and their decision to start dating and eventually immigrate to the United States along with her stepmother Teta Elzbieta, and their extended family after hearing how their relative Jokubas Szedvilas is making money there. In the second and third chapters Jurgis and Ona settle in Chicago's infamous Packingtown district, where from the start, Jurgis takes a job at Brown's slaughterhouse. (Brown was a pseudonym for Armour and Company.) Jurgis believes when he immigrates to the United States that it will be a land of more freedom, but soon his employer's treatment of him disappoints him. Alas, they have to make compromises and concessions to survive. Due partly to illiteracy in English, they quickly make a series of bad decisions that cause them to go deep into debt and fall prey to con men. The most devastating decision comes when, in hopes of owning their own home, the family falls victim to a predatory lending scheme that exhausts all their remaining savings on the down-payment for a sub-standard slum house that (by design) they cannot possibly afford. The family is evicted and their money taken, leaving them truly devastated. The family had formerly envisioned that Jurgis alone would be able to support them in the United States, but one by one, all of them—the women, the young children, and Jurgis' sick father—have to find jobs in order to contribute to the meager family income. As the novel progresses, the jobs and means the family uses to stay alive slowly and inevitably lead to their physical and moral decay. A series of unfortunate events—accidents at work, along with a number of deaths in the family that under normal circumstances could have been prevented—leads the family further toward catastrophe. One injury results in Jurgis being fired; he later takes a job at Durham's fertilizer plant. (Durham was a pseudonym for Swift and Company.) The family's tragedies cumulate when Ona confesses to Jurgis, who is suspicious of her frequent absences from home, that her boss, Phil Connor, had raped her, and made her job dependent on her giving him sexual favors. In revenge, Jurgis later attacks Connor, leading to his arrest and imprisonment by the corrupt judge Pat Callahan, who sides with Connor against Jurgis. After his stint in jail, Jurgis returns home, only to find out that his family has been evicted. He finds his family at a relative's house; Jurgis also discovers Ona in labor with her second child. Ona dies in childbirth from blood loss at the age of eighteen. Jurgis lacked money to pay for a doctor; so Ona has to rely on the greedy and incompetent Madame Haupt, whose carelessness leads to Ona's death. Soon after their first child drowns in the muddy street, causing Jurgis to flee the city in utter despair and turn to drinking. At first the mere presence of fresh air is balm to his soul, but his brief sojourn as a hobo in rural United States shows him that there is really no escape—even farmers turn their workers away when the harvest is finished. Jurgis returns to Chicago and holds down a succession of jobs outside the meat packing industry—digging tunnels, as a political hack, and as a con-man—but injuries on the job, his past and his innate sense of personal integrity continue to haunt him, and he drifts without direction. One night, while looking for a warm and dry refuge, he wanders into a lecture being given by a charismatic Socialist orator, and finds a sense of community and purpose.