High schooler Avery Anderson moves with her family from Washington, D.C. to her mother’s hometown of Bardell County, Georgia to help care for her dying grandmother, Mama Letty. Avery is concerned how she will be treated in a small Southern town, given that she is pansexual and biracial. Zora, Avery’s mother, has not brought her family to Bardell since Avery was a small child, and her relationship with Mama Letty is fraught.
In Bardell, Avery gets to know Mama Letty and her neighbors Carole and Simone. Simone is in Avery’s class at Beckwith Academy, and the two girls are some of the few students of color at a predominantly White school. Beckwith is named for Richard Beckwith, who is honored with a statue in front of the school despite being known as a racist. At Beckwith, Avery befriends Simone and Simone’s friend Jade Oliver, whose wealthy family are highly influential in Bardell.
Jade’s family owns the Draper Hotel, which caters to tourists who visit Bardell in search of a southern fantasy. Jade has painted a mural outside the hotel in honor of her late mother Amelia, who was murdered under mysterious circumstances. People in town suspect Jade’s father, Lucas, killed his wife in order to marry his mistress, Tallulah.
Avery tells Jade and Simone about her White ex-girlfriend Kelsi, whom Avery broke up with after Kelsi repeatedly displayed casual racism against her. Jade explains that she and Simone have sworn off dating to prioritize their friendship. Avery is attracted to Simone, but she wants to respect the “no dating” rule. Later, Simone comes out to Avery as a lesbian. Simone then panics and refuses to talk to Avery about it further. Still, the two eventually begin a romantic relationship in secret.
Mama Letty and Zora continue to argue constantly. Avery tries to develop a relationship with her grandmother and to learn some of the secrets that Letty keeps. Mama Letty tells Avery about Avery’s grandfather, Ray, who died before Zora was born. As Mama Letty begins to open up to Avery, she gradually reveals the truth of Ray’s death: Ray was murdered by the police and the Ku Klux Klan.
Jade invites Avery to her home, the Ivy Rose Plantation, which has been in the Oliver family for generations. While there, Avery is swept up in the Oliver family dinner. She meets Jade’s extended family, and when Tallulah is repeatedly condescending and rude about Mama Letty, Avery confronts her about her affair with Lucas and the rumors surrounding Amelia’s death. Tallulah dislikes Mama Letty because Letty once worked at a pharmacy and refused to let Tallulah take a soda for free. When Avery returns home, Mama Letty tells her that the Olivers were the family who murdered Ray.
Zora takes Avery to her favorite restaurant in Bardell, the Renaissance, which is a haven for Black LGBTQ+ people in town. She explains to Avery that Mama Letty was neglectful and abusive when Zora was a child due to Letty’s grief for Ray, and Zora is still struggling to forgive her. As a teenager, Zora befriended and eventually began an emotional relationship with Simone’s mother, Carole, until Mama Letty forced her to end the relationship.
Avery goes to the County Fair with Simone and Jade, and Jade and her younger brothers see Avery and Simone kissing. Jade is hurt that they would keep this secret from her, and that Simone would break the “no dating” rule. She confronts them, and Avery angrily responds by revealing what the Olivers did to Ray. Jade’s brothers tell Tallulah about Simone and Avery, and Tallulah in turn tells Carole. Simone, afraid of what Carole will say, asks Avery to break curfew and drive somewhere with her. They spend all night at the Renaissance.
When Avery and Simone return home, Carole yells at Simone and accuses Avery of corrupting her into homosexuality. Carole keeps Simone home from school the following Monday, and Jade gives Avery the silent treatment. Avery feels aimless and lonely.
Avery’s family spends Thanksgiving at Kisabee Island, where Mama Letty once went with Ray. Mama Letty, Zora, and Avery all reconcile and come to terms with the past. On the same trip, Mama Letty’s health declines, and she has to go to the hospital. She dies in the hospital, surrounded by her family as well as Simone and Carole.
As Avery prepares for the funeral, she finds evidence that Mama Letty killed Amelia Oliver. She decides to keep this secret. At the funeral, she makes up with Jade, who promises to try to persuade the Bardell Historical Society to erect a monument in honor of Mama Letty and Ray.
The Historical Society rejects the proposal, but Bardell is filled with monuments in the form of the landscape where Mama Letty and Ray lived their lives. Students at Beckwith tear down the statue of Beckwith himself, Carole begins the process of accepting Simone’s sexuality, and Simone achieves a dream of hers to attend Spelman College.
The novel ends with a flashback in which Mama Letty kills Amelia, passes the train station where Ray used to work, and returns home.