It is the year 2024, the night before Lauren Olamina’s 15th birthday (and Lauren’s father’s 55th). Lauren has a dream in which she is teaching herself to fly, but ends up flying into a wall of fire. Later, she and her stepmother, Cory, discuss the fact that now there is no light pollution, and people can see the stars again. Although Lauren has stopped believing in her father’s religion, she is about to let herself be baptized. Lauren and the other kids being baptized are making a special trip beyond their neighbor wall to a real church for the occasion. They live in Robledo, a city 20 miles outside Los Angeles. The people living outside their neighborhood wall are homeless, mutilated, and wounded, which makes it difficult for Lauren to be around them. She suffers from hyperempathy as a result of her mother’s drug abuse during pregnancy, a condition that means she feels other people’s pleasure and pain.
Meanwhile, an astronaut named Alicia Leal has died on a mission to Mars. One of the presidential candidates, Christopher Donner, has vowed to eradicate the space program in order to save money, but Lauren believes that space is the future. Mrs. Sims, a devoutly Christian woman in Lauren’s neighborhood, has killed herself even though she believes suicide is punished by hell. Christopher Donner wins the election.
A year later, in 2025, a three-year-old girl in the neighborhood called Amy Dunn sets fire to her family’s garage. Amy is the product of incestuous rape; her mother, Tracy, was only 12 when she became pregnant with her. Mrs. Sims’ cousins Wardell Parrish and Rosalee Payne move into her empty house. Lauren doesn’t trust the Payne-Parrish family. Lauren goes to target practice along with her boyfriend Curtis Talcott and his brother Michael, as well as Peter Moss. Peter is the son of Richard Moss, a “total shit” with three wives who practices his own highly patriarchal religion, a mix of West African traditions and Old Testament teachings. The group encounter a feral dog; Lauren’s best friend, Joanne Garfield, panics. Lauren shoots the dog and almost collapses from the pain.
It rains for the first time in 6 years. The next day, Lauren learns that Amy has been shot dead by someone shooting through the neighborhood gate. Joanne comes over for lunch in Lauren’s room, and the two discuss the future of the neighborhood. Lauren admits that she doesn’t think the neighborhood will be secure for much longer and that she has been reading books to help her prepare for survival. Joanne is skeptical and accuses Lauren of reading “too many adventure stories.” Joanne tells her mother about this conversation, which causes Lauren’s father to have a stern conversation with her. However, he eventually agrees to make emergency “earthquake” packs and set up a nightly neighborhood watch.
Lauren has devised a name for her own religious beliefs: Earthseed. She believes that the future of this religion is to spread human life throughout the universe. She collects her writings about Earthseed into a single notebook and hopes that one day she will use this to teach others. The day before Lauren’s 16th birthday, Tracy walks out of the neighborhood gate and never returns. Lauren knows that people in the neighborhood expect Lauren to marry her boyfriend Curtis and have children, but this is not the future she wants for herself.
Lauren’s 12-year-old brother Keith steals Cory’s key and leaves the neighborhood. When he eventually returns, he is wounded and filthy, and some of his clothes have been stolen. Lauren’s father is furious; Keith sulks. Some time later, Lauren’s father and Cory give Keith a BB gun for his birthday. Keith disappears, and comes back two days later with new clothes and shoes. He then goes out and returns again with a roll of cash.
A year later, in 2026, Keith is almost 14 and very tall. He is living in a building outside the neighborhood. He and Lauren have a friendly conversation while she is making dinner; even though she knows he is hiding the fact that he is involved in illegal activity, their relationship is closer than before. Keith tells Lauren about a drug called pyro that makes people set fires. Two days later, Keith is found dead. His body has been mutilated, which suggests he was killed by drug dealers. Cory can’t stop crying, but neither Lauren nor her father cry.
Meanwhile a company called KSF has taken over the coastal city of Olivar and is inviting people to come and live there. Lauren’s father is skeptical about this scheme, but Cory expresses interest in moving there. Lauren decides to call her book of Earthseed scripture Earthseed: The Book of the Living.
Joanne and her family are accepted by KSF to move to Olivar. A few days later, Lauren’s father doesn’t come home from work. Lauren and other neighborhood residents search for him, but find nothing. Lauren preaches at the Sunday church service in place of her father.
Lauren’s family hold a funeral for her father even though they still don’t know what happened to him. Lauren and Curtis have sex and discuss going north together. A few days later, someone sets fire to the Payne-Parrish house, and all the Paynes die in the blaze. Wardell stays at Lauren’s house, where he refuses to eat and behaves erratically.
Seven months later, Lauren wakes to the smell of burning. Intruders have driven a truck through the neighborhood gate and pyro addicts with their skin painted bright colors have set fire to the buildings. Lauren runs through the neighborhood, past dead bodies. She hides in an abandoned garage outside the neighborhood gate.
In the morning, Lauren returns to find the neighborhood destroyed. She goes into her house and takes essential supplies including clothes, bathroom items, money, and her emergency pack. She sees the bodies of Richard Moss and Michael Talcott lying on the street. She is approached by Zahra Moss, Richard’s youngest wife, and Harry Balter. Zahra tells Lauren that Cory and her brothers are all dead. Lauren tells Zahra that Richard is dead, and Zahra bursts into tears. Zahra explains that Richard “bought” her from her mother when she was 15 and homeless. Lauren tells Zahra and Harry that she is planning on going north. Harry agrees to come along, and Lauren decides to dress in drag in order to attract less attention. Zahra eventually agrees to come too.
Lauren, Harry, and Zahra stock up on essential supplies at a nearby mall. They then journey to the 101, where there are hundreds of other people walking north. They are careful not to trust the people around them, knowing that even those who look harmless can be secretly dangerous. At night, they take turns keeping watch. During Harry’s turn, a man attacks him, trying to steal his gun. Lauren cracks the man’s skull with a rock, then slits his throat in order not to feel his pain. This upsets Harry, but Lauren insists that she wouldn’t have killed him unless she knew he would die anyway. She also tells Harry and Zahra about her hyperempathy, and Zahra notes that where she comes from, most babies were born with drug-related abnormalities. Later, Lauren shows Harry the first lines of Earthseed scripture: “All that You touch / You change, / All that you Change / Changes you… God is Change.”
The trio see another enormous fire as they walk north. That night, Harry and Zahra have sex during Harry’s watch. Lauren sternly urges Harry to be more careful. Back on the road, they intervene in the attempted robbery of a young interracial family: two parents and their baby. Lauren believes the family will join them, as they are natural “allies.” They reach the ocean, and Lauren manages to set up a water filtration system to make the ocean water drinkable. A dog approaches the interracial family, who have camped nearby, and Lauren shoots it. The family come over and introduce themselves: the man is called Travis, the woman Natividad, and their baby Dominic. Lauren reads them some Earthseed verses.
Later, the group are camping on a new beach in Santa Barbara County, and Travis and Lauren are discussing Earthseed. Travis is skeptical, but curious. Lauren explains that Earthseed’s “Destiny” is to “take root among the stars”—to colonize other planets—and that this is Earthseed’s version of “heaven.” A week later, she writes that Travis is her first convert, and Zahra her second. She resolves to stay on lookout for new people to join the growing Earthseed community, as the more people in the group, the safer they will be.
A few days later, there is an earthquake. Lauren befriends a handsome 57-year-old black man named Bankole. The group rescue two young white women from a semi-collapsed house, and immediately after are attacked by four men. They manage to fight the men off. The white women introduce themselves as Allie and Jill Gilchrist, sisters who are on the run from an abusive father who forced them into prostitution. Harry introduces the group as Earthseed. Lauren reflects that she likes Bankole too much and must be cautious.
Days later, Bankole rescues a three-year-old child, Justin Rohr, who has just been orphaned. That night, Bankole and Lauren kiss before Lauren goes on her watch. Allie forms a bond with Justin, and Jill explains that Allie had a baby son but their father killed him.
The group stops at the San Luis Reservoir, which has not yet totally dried up. Bankole and Lauren spend time alone discussing Earthseed. Bankole explains that he is a widower and a doctor and that, like Lauren, he used to live in a gated community. They spend the next day talking, reading, writing, and having sex. Lauren spends time teaching Jill, Allie, and Zahra to read and write.
The group spend a week walking up the I-5. Bankole tells Lauren that he has property in Mendocino, a farmhouse with 300 acres of land. His sister Alexandra is currently living there with her husband, Don, and their three children. Bankole insists that Lauren joins him there, but Lauren replies that she is committed to Earthseed. Lauren then tells Bankole about her hyperempathy.
In the night, two intruders enter the group and sleep alongside them: a woman and her young daughter. The group decide to let the intruders join them, and the woman introduces herself as Emery Solis and her daughter as Tori. Emery and Tori were enslaved on a farm along with Emery’s husband and two sons; however, Emery’s husband grew sick and died, and shortly after her sons were kidnapped. A few days later, two more formerly enslaved people join the group: Grayson Mora and his daughter Doe. Bankole notes that there is something strange about Emery, Tori, Grayson, and Doe.
Days later, the group are attacked again. Lauren is shot and Jill is killed trying to save Tori. After regaining consciousness, Lauren realizes that the four new members of the group all have hyperempathy as well. She discusses the condition with Grayson, and he formally agrees to join the Earthseed community. Emery explains that the slave “bosses” like it when enslaved people have hyperempathy. The group walk through the smoke from a large fire and Lauren becomes convinced that they will die. However, they survive, and soon after reach Bankole’s property. They arrive to find that the farmhouse has been burned to the ground.
The group find five skulls, although at first Bankole refuses to believe that Alexandra and her family are dead. The group argue over whether they should stay on the property or keep moving north. Eventually, the group decide to stay, and hold a mass funeral for all the loved ones they have lost. They plant acorns for each dead person and read a mix of Bible passages, Eathseed verses, poems, and songs. They decide to call their new home “Acorn.” The book ends with the Parable of the Sower from the Bible, a verse about the importance of sowing seeds on “good ground.”