Orleanna Price, the mother of the family, narrates the introductory chapter in five of the novel's seven sections. The narrative then alternates among the four daughters, with a slight preference for the voice of the most outspoken one, Leah. The four girls increasingly mature and develop differently as each adapts to African village life and the political turmoil that overtakes the Belgian Congo in the 1960s.
The Price family packs up their belongings for their flight to the Congo, where they are going to spend a year as the family of a missionary. However, shortly before leaving, they are informed that they are limited to 44 pounds of luggage per person. The Southern Baptist Mission League suggests they solve this problem by leaving for the airport wearing many layers of clothing, hiding household items among the layers of clothes to lighten their luggage. This is the first problem of many the Price family will face.
The Price girls, Rachel, Leah, Adah and Ruth May, and their father, Nathan, attend their first church service in the village of Kilanga, and they realize how different their culture is from that of the Congo. For example, 14-year-old Leah helps her father plant a "demonstration garden", and it immediately receives criticism from Mama Tataba, whom the family has engaged as a live-in helper. Nathan tries to hold an impromptu Easter celebration in hopes of baptizing numerous people, but he is not successful in baptizing even one, as the river along the village, where he plans to hold the baptism, is infested with crocodiles.
Leah and her twin Adah begin to spy on Eeben Axelroot, the pilot who conveyed the family to Kilanga, and Nathan tries to convince Congolese men, one by one, to convert to Christianity. Meanwhile, five-year-old Ruth May befriends the village children. She finds out about Axelroot's business with the diamonds after breaking her arm.
After Mama Tataba departs, an orphan boy named Nelson becomes the family servant. Nathan and Leah go to Leopoldville (present day Kinshasa) to witness what is going on with the independence in the Congo. Methuselah (a parrot the Prices adopted from the previous missionary) dies, and Adah finds his feathers. Ruth May becomes very sick and lies in bed for the majority of the day. Leah begins to spend a lot of time with Anatole, Kilanga's teacher, discussing topics such as justice and the Congo. Leah wants to participate in the hunt, which upsets the village elders, as it would go against their custom, but she eventually is allowed to participate and even hunts an antelope.
The girls all gather together in the morning to check out the chicken coop. Inside they find footprints and a green mamba snake. A scream and gasp is heard from Ruth May, who has been bitten by the snake. The girls watch her turn cold and blue before she passes away. Orleanna becomes filled with guilt over Ruth May's death.
The rest of the sisters in the Price family go through many different life changes: Adah dedicates herself to getting a scientific education back home (she is hemiplegic and wants to learn more about the condition); Leah marries Anatole and they start a family together; Rachel remains very self-centered, goes through a string of marriages, and starts a business; and Nathan dies in his unsuccessful mission.
The story ends with a final chapter from Ruth May reflecting on her sisters and mother attempting to visit her grave but not being able to find it, and a woman telling them a place named Kilanga never existed. She watches her sisters and her mother, and has seen how they have matured; she has matured as well. Through her death, she finally is able to understand the Congolese term muntu, which describes the concept of unity and how all life is connected in some way. She understands that she is muntu, and a part of all that is around her. Ruth May only wants her mother to understand the concept and for her to move on. She asks for her mother to forgive herself and not live with the guilt anymore.