Truman Held arrives in Chicokema, Georgia, to meet up with his former lover, Meridian Hill. He first sees her staring down a manned tank as she escorts local schoolchildren to a sideshow attraction displaying a mummified woman, on a day the children, mostly poor and black, are forbidden to attend. After collapsing and being brought home unconscious, she and Truman catch up. The action then shifts, in a flashback, to New York City, where, ten years ago, Meridian is unwilling to assert that she will kill on behalf of a black revolutionary organization, to the dismay of the others assembled. Then, even further back in time, Meridian, at the age of thirteen, is unwilling to accept Jesus into her life, a decision that prompts her mother to withdraw her love. Meridian, back in the present, has decided to return to her roots as a former civil rights worker, and vows to live and work amongst the people. Truman does not understand the mysterious illness that grips her, causing her to experience fainting spells and paralysis. He admits his inability to let her go.
The action shifts to Saxon College, where Meridian and Anne-Marion first meet. While canvassing a local neighborhood for voters, Meridian meets the Wild Child, a pregnant, homeless teenager. Meridian captures her, then bathes and feeds her. When Meridian makes phone calls to find additional assistance for her, the Wild Child escapes, runs out into the street, is struck by a car, and dies. Meridian, Anne-Marion, and other students and neighborhood residents carry the Wild Child’s casket, leading the funeral cortege onto the campus grounds. But the president of the college denies them access to the chapel for the services. That night the students riot and chop down the Sojourner, the school’s iconic magnolia tree.
In another flashback, Meridian’s father deeds sixty acres of his farmland back to the Cherokee who once owned it, specifically to Walter Longknife. He camps on the parcel for a brief period in the summer then cedes ownership back to Meridian’s father. The area, with its serpent-shaped mound, is then made into a historical site that bars blacks. Meridian and her father are no longer allowed access to the pit in the serpent’s tail where they experienced the swooning, paralysis, and strange manifestations that are part of their unique family condition.
As a teenager, uninformed about sex, Meridian becomes pregnant, marries, and drops out of school to have the baby boy, who makes her feel indifferent at best. Around the time her marriage to Eddie is dissolving, Meridian notices the presence of white civil rights workers in a black neighborhood. Later, the house in which they are staying is bombed. The incident spurs Meridian to volunteer for the cause. At the headquarters, she meets Truman. Soon they are demonstrating together and getting beaten, arrested, and jailed. Meridian’s mother disapproves of Meridian’s radical political activities. Unexpectedly, Meridian is offered a scholarship to Saxon College. Her friends attempt to convince her mother that it is a great opportunity for Meridian. Giving up Eddie Jr., Meridian starts school but is plagued with the guilt that always dogs her.
Meridian tries her best to battle loneliness and adjust to college life. After the Wild Child incident, she moves off campus, actively continuing her civil rights protests and demonstrations. She also falls in love with Truman. The two begin dating, but their newfound bliss as a couple is compromised by the arrival of college students—white women—from the North who volunteer to assist the movement. Many invoke a racial patronage or romantically fetishize the foreign, black culture that they are fully confronting for the first time. Truman is taken by one of the new arrivals, Lynne, and the two begin dating. Although Truman and Meridian briefly resume sexual relations, Truman continues to pursue his budding relationship with Lynne. Pregnant, Meridian has an abortion and gets her tubes tied. After Lynne leaves, Truman attempts to rekindle his former love for Meridian, asking her to have his children. Meridian, in response, strikes him with her bookbag, cutting his cheek.
With graduation approaching, Meridian again falls ill, losing her sight and lapsing into unconsciousness. She stays in bed for a month. Miss Winters, one of Saxon’s few black instructors, nurses her back to health. Anne-Marion, who has also been at Meridian’s side, eventually concludes that she is incapable of loving Meridian and turns her back on her friend. Truman and Lynne, now married, are living in Mississippi, where her whiteness begins to endanger them and the movement when a fellow rights worker, Tommy Odds, has the lower half of one of his arms shot off. Increasingly, Lynne is excluded from the marches and meetings. Despite having a daughter, Camara, Truman grows more and more distant from his wife. He drives to Alabama to visit Meridian. Newly obsessed with his former lover, he tries to win her back, but Meridian spurns his advances. After the death of Camara, Lynne visits Meridian, whose illness has advanced and claimed most of her hair. Lynne is bitter over the slow dissolve of her marriage and the way her once-idealistic life has turned out. She has come in search of Truman, whose visits to Meridian have become more frequent.
The action then shifts, in flashback, to Lynne’s younger years, when she leaves her family for her new life with Truman and the movement. After the shooting, Tommy Odds rapes her. He returns with three friends and encourages them to do the same, but they refuse. Lynne, hysterical, entertains thoughts of leaving and tells Truman what happened, but he doesn’t believe her. Tommy tells Truman that Lynne is with him solely to atone for her sins, out of guilt for the racism blacks had suffered for centuries. Lynne and Truman grow increasingly distant, as Lynne eventually seduces or succumbs to the sexual advances of his friends and other men in the community. Eventually, the men tire of her and, pregnant, she moves to New York and lives on welfare. Truman also moves to New York, where he becomes an artist. When Lynne comes to his apartment uptown to tell him that Camara has been attacked by a man and hospitalized, she discovers that he is living with a young blond woman. After Camara dies, Truman sends for Meridian, who arrives to comfort him and Lynne. Lynne recalls her impressions of southern Jews and the way they treated her. She eventually resolves she has no regrets for leaving her past, and its association with white oppressors, behind.
The novel’s final section opens with the Atlanta funeral cortege of Martin Luther King, Jr. Eight years later, Meridian struggles with questions of radicalism and how the movement ultimately turned out. Truman finds it easier to leave such issues alone. Meridian remains in her small town, advocating for the black residents to vote and try to change their lot. She recalls the time she took to regularly attend church services. Once, an old man, whose radical son had been killed while working for the movement, addressed the congregation. Meridian regained her wavering desire to kill on behalf of the rights of blacks. She and Truman continue their voter-registration drives in earnest. Truman tells Lynne he loves her and will support her as a friend. Truman asks Meridian to love him as she once did. Meridian readily asserts that she does love him but that her feelings have changed. Cured of her illness, Meridian prepares to move on, leaving Truman behind to continue the work that she started in Chicokema. Reading the poems she has posted on the wall, Truman falls to the floor in a swoon. Upon awakening, he concludes that he must take up the internal struggle of which Meridian has finally freed herself.