Lena Grove, a pregnant and unmarried young woman, is traveling barefoot from Alabama to Mississippi. On the journey she encounters two men, Winterbottom and Armistid; Armistid offers her a ride and then invites her to stay the night at his house. Lena explains that she is looking for the father of her child, Lucas Burch, who left Alabama and promised to send for her but seemingly never did. She is confident that she will find him and that the family will be reunited by the time the baby comes. Armistid’s wife, Martha, takes pity on Lena and gives her the money she’s been saving up from selling eggs. The next day, Lena arrives in the town of Jefferson and sees a house burning in the distance.
Byron Bunch, a worker in the Jefferson planing mill, recalls when a stranger showed up and began working at the mill. The stranger seemed to come from nowhere, and had the odd name of Joe Christmas. Soon Christmas moves into a “negro cabin” on the property of the middle-aged white “spinster” Joanna Burden. Shortly after, another newcomer to Jefferson and the planing mill, Joe Brown, moves into the cabin as well. Brown starts running a business selling bootleg whisky, and people suspect Christmas is involved too.
Byron has worked at the planing mill for seven years, although his only friend in Jefferson is the disgraced minister Rev. Gail Hightower. When Lena arrives in Jefferson, she finds Byron at the planing mill, having been told he was Lucas (in reality, there was a mix-up due to the similarity of the two men’s last names, Bunch and Burch). Byron falls in love with Lena, and agrees to help her find Lucas. However, they quickly realize that Lucas is actually Joe Brown, and that he’s been living under this fake name.
Hightower fell from grace due to the actions of his wife, Mrs. Hightower, who had an affair with another man and ended up dying in Memphis (it is unclear whether this was murder, an accident, or suicide). Following this scandal, Hightower was pressured into resigning as a minister and leaving Jefferson. Although he resigned, he refused to leave the town, even after being violently intimidated by the KKK. Eventually everyone forgot about the scandal and left Hightower alone to lead a reclusive life.
Hightower and Byron discuss the burning house, which is Joanna’s. Byron helps Lena gain lodging at Mrs. Beard’s boarding house, where he also lives. It then emerges that Joanna’s dead body was found in the house with the head almost completely sawed off. Her nephew in the North offers a reward of $1000 for whoever finds the murderer. At this point, Brown tells the sheriff that Christmas killed Joanna and that he once confessed to Brown that he’s black (though he passes as white).
Meanwhile, Christmas is in a wild, restless mood, and keeps telling himself that he had to kill Joanna because she started praying over him. The narrative then jumps back in time to Christmas’s childhood, when he was only five years old and living in an orphanage. The live-in dietician and janitor in the orphanage despised Christmas and were desperately waiting for the moment when the truth of his racial identity would be revealed. One day the janitor abducts Christmas and brings him to an orphanage for black children, but the police retrieve him and bring him back to the white orphanage.
Shortly after, Christmas is adopted by a severe, fanatically religious man named McEachern. When Christmas is 8, McEachern beats him viciously for failing to memorize his catechism. McEachern’s wife Mrs. McEachern is much kinder to Christmas, secretly bringing him food and trying to protect him from her husband’s punishments, but Christmas adamantly rejects her kindness.
At 17, Joe meets a young woman, Bobbie, who works as a waitress at a dingy restaurant in town (which is actually a brothel). He develops a crush on her but doesn’t speak to her until a year later, when he is 18. After awkward initial reactions, the two begin dating. After they have sex for a few weeks, Christmas reveals that he has black heritage, but Bobbie doesn’t believe him. Christmas steals money from Mrs. McEachern to buy Bobbie gifts. Eventually Christmas learns that Bobbie is a sex worker; at first he is horrified and slaps her, but afterward he keeps seeing her, and starts calling her his “whore.” One day, Christmas and Bobbie are at a dance when McEachern shows up and starts threatening them. Christmas strikes his adoptive father with a chair, seemingly killing him.
Christmas goes home to take more money; while there he sees a worried Mrs. McEachern but does not tell her what happened to her husband, instead only laughing cruelly. He brings Bobbie the money, saying he assumed that they would now get married, but Bobbie screams that Joe is a “n_____ son of a bitch.” A stranger who is also in the house knocks out Christmas, and when Christmas comes to, Bobbie is gone.
Christmas spends 15 years living in different parts of the country (and in Mexico), sometimes as a black man and sometimes as white. While in Chicago and Detroit he completely integrates into black communities and tries to expel the whiteness from him, although he is not successful. He arrives in Jefferson at the age of 33, and meets Joanna after he trespasses into her house and eats food in her kitchen. Instead of being angry, Joanna welcomes him; soon after the pair begin a sexual relationship, and Christmas moves into the cabin on Joanna’s property.
Joanna tells Christmas the story of her family. Her grandfather, Calvin Burden, Sr., was born in New Hampshire but ran away from home at the age of 12. He was an abolitionist who killed a man during an argument about slavery. His son, Nathaniel, inherited his father’s hatred of slavery. At the age of 14 Nathaniel also ran away. He married a Mexican woman named Juana and had a son, Calvin, Jr. Both Calvins ended up being killed in Jefferson by a Confederate soldier who was a former slaveholder in an argument about black enfranchisement. The fact that both Calvins are buried in Jefferson led Nathaniel and Joanna to stay in the area despite the fact that they have never been welcome there.
Christmas and Joanna’s relationship was at first passionate, but as time goes on and Joanna gets older—and, it is implied, goes through menopause—she becomes more conservative and religious. This infuriates Christmas, who does not want to marry her or have children with her. One day, when Joanna repeatedly asks Christmas to pray with her, he ends up killing her (although this exact moment is not described in the novel, leaving it slightly ambiguous what happened).
Before long, the people of Jefferson discover that Joanna’s house is on fire and find her body inside. People begin to speculate over who killed her, with many believing that it must have been a black person. After Brown gives his statement to the sheriff, a manhunt begins searching for Christmas.
Byron decides to bring Lena to live in the cabin on Joanna’s property, because it is the closest thing Brown has as a home to give her. (Neither Byron nor Lena have yet been in contact with Brown, who is currently fixated on getting the reward money for catching Christmas.) Hightower warns Byron about trying to insert himself in between Lena and Brown.
A black man rushes to the sheriff and tells him that Christmas has just entered a black church in Mottstown (the next town over from Jefferson) and threatened the minister before attacking one of the congregants, fracturing his skull. The sheriff quickly goes off in pursuit of Christmas, who has by now not eaten or slept for several days.
There is an elderly couple living in Mottstown by the name of Mr. and Mrs. Hines. People in the town regard them as strange. When Mr. Hines sees Christmas being held captive by a group of men in Mottstown, he has a kind of fit, demanding that Christmas be lynched. Mrs. Hines arrives and calms her husband down. She tries to visit Christmas in jail, but only manages to catch a brief glimpse of him as he is being taken away to the Jefferson jail by the Jefferson sheriff.
The next day, Byron brings Mr. and Mrs. Hines to Hightower’s house. They explain that Christmas is their grandson, the child of their daughter, Milly, and a Mexican man who Mr. Hines was convinced was black. Due to this conviction, Mr. Hines tried to get Milly to have an abortion, and after failing in that, stole the baby as soon as it was born and brought it to an orphanage. He then took a job as a janitor at the orphanage to keep an eye on the child, while telling Milly and Mrs. Hines that he was dead. (It is thus revealed here that the janitor who abducted Christmas was Mr. Hines.)
Mrs. Hines explains that she doesn’t intend to stop Christmas from being punished if he truly committed the murder, but she wants him to die in a “decent,” legal way, rather than being lynched. Byron asks Hightower to provide an alibi for Christmas, saying that he was with him during the night of the murder. Hightower is furious at this request and refuses.
The next morning, Lena goes into labor and Byron asks Hightower to tend to her while Byron fetches the doctor (years ago, Hightower successfully helped a local black woman give birth using information from a book). Hightower goes to the cabin and helps Lena deliver the baby. Mrs. Hines is there too and holds the baby, who she keeps calling “Joey” while calling Lena “Milly.”
Byron tells the sheriff about the Lena/Brown saga and the sheriff assigns his deputy, Burford, to forcefully bring Brown to see Lena and his newborn son. Byron then rides off, intending to leave Jefferson for good. When Brown sees Lena lying in the cabin with the baby, he is shocked, and soon makes another run for it. He finds a local black man and scribbles a note to the sheriff, asking the sheriff to give the man the reward money so he can bring it to Brown.
The District Attorney, Gavin Stevens, who has been presiding over the Grand Jury in charge of Christmas’s trial, tells a friend of his the story about Christmas’s final hours. Christmas managed to escape jail and went to Hightower’s house, probably because Mrs. Hines had told him that Hightower would save him. However, a local fanatically patriotic man named Percy Grimm found Christmas in Hightower’s house and lynched him.
The penultimate chapter tells the story of Hightower’s family. His grandfather was a Confederate Civil War hero who was idolized within Hightower’s household, particularly by Hightower’s nanny, Cinthy, who had formerly been enslaved by his grandfather. Hightower’s father was the total opposite of his grandfather: he was a teetotaler abolitionist who was first a minister and then a doctor after the Civil War. Hightower has always been obsessed with the past, and particularly with his grandfather, to a point that it has actually interfered with his ability to live a normal life. The chapter ends with Hightower in a dramatic reverie in which he possibly dies.
In the final chapter, a furniture seller describes picking up a man, woman, and child, who are soon revealed to be Byron, Lena, and her baby. They are ostensibly still looking for Lucas, and catch a ride with the furniture seller, that night sleeping in his truck. During the night, the furniture seller hears Byron trying to get into the truck with Lena and being gently rejected. Byron then disappears for a bit but eventually comes back, saying he’s come too far to give up now. The furniture seller comments that it doesn’t seem as if Lena is actually searching for anything, but is rather just determined to stay on her endless journey.