In a post-apocalyptic Chicago, people have been divided into five factions: Abnegation, who were the selfless; Amity, who were the peaceful; Candor, who were the honest; Dauntless, who were the brave; and Erudite, who were the intelligent. All sixteen-year-olds are tested to determine the faction that suits them best but end up selecting their own faction at the annual Choosing Ceremony. Those who do not complete initiation become "Factionless" and live on the streets as outcasts.
Sixteen-year-old Beatrice Prior cannot choose before taking the test. Her inconclusive test results- Abnegation, Dauntless, and Erudite- mark her as "Divergent," and the test administrator, Tori, warns her never to tell anyone. Agonizing over her future, Beatrice decides to leave Abnegation, her original faction, and join Dauntless. Her brother, Caleb, chooses Erudite, much to her and their family's shock.
The new Dauntless initiates jump onto a moving train to Dauntless headquarters and are instructed to jump onto the roof. Most make it, but one initiate falls to her death, and another is too afraid to jump. When they are later ordered to jump into the compound entrance, Beatrice jumps first. Reaching the bottom, she tells the instructor, Four, that her name is Tris.
Four explains that only the top ten Dauntless initiates will stay, and the rest become Factionless. Tris befriends fellow initiates Christina, Will, and Al but comes into conflict with others like Peter, Drew, and Molly.
The Willis (or Sears) Tower, one of several landmarks Roth describes within post-apocalyptic Chicago, the novel's setting.In the first stage of initiation, they are trained in guns, knives, and hand-to-hand combat. Despite her lack of physical strength, Tris finishes in sixth place. A relationship emerges between Tris and Four, and Tris is pummeled by Peter in a fight. After the first-stage rankings are announced, the second-place Peter stabs the first-place Edward in the eye. Edward leaves to become Factionless, followed by his girlfriend Myra, which allows Peter to take Edward's place as the first-place initiate.
On Visiting Day, Tris' mother, Natalie, tells Tris to stay strong but not to bring too much attention to herself during training.
Erudite stirs dissent against the city's Abnegation leadership and accuses its leader, Marcus, of abusing his son. The rumors are fueled by the fact that Marcus's son, as well as Tris and Caleb, have all left Abnegation, which is also alleged to be hoarding supplies.
The initiates enter the second stage and face hallucinations based on their deepest fears. Tris' Divergent abilities give her an advantage and earn her the top rank. Peter, Molly, Al, and Drew attack Tris, threaten sexual assault, and nearly throw her to her death, but Four intervenes. Al begs Tris's forgiveness, but she rejects him, and he later dies by suicide.
The final stage gathers the initiates' fears into a simulated "fear landscape" to test their acquired skills. Tris and Four grow closer, and he lets her into his own fear landscape. She discovers that he has only four fears, hence his nickname. In Four's final fear, Tris learns he is Marcus's son and the claims of abuse were true. Four uncovers Erudite's plans to use Dauntless to stage an attack on Abnegation.
Tris overcomes her fear landscape, and the Dauntless initiates are injected with a "tracking" serum. Tris shares her feelings for Four and is later ranked first at the initiation ceremony.
A junction on the Chicago "L", one of modern Chicago's train systems. The Dauntless demonstrate their fearlessness by jumping on and off moving trains throughout the novel.The serum transforms the Dauntless into hypnotized soldiers to attack Abnegation. Tris and Four's Divergent abilities allow them to remain unaffected by the serum and escape to the Abnegation compound. Tris is shot, and they are captured. The Erudite leader Jeanine Matthews, the mastermind of the attack, injects Four with an experimental serum that overrides his Divergence. Under Jeanine's control, Tobias oversees the attack from the Dauntless control room. Tris is almost drowned in a tank but is rescued by her mother, who reveals that she is also Divergent while helping Tris escape. Tris is forced to kill Will, who attacks her under the influence of the simulation.
She finds her and Four's fathers and explains the truth behind the attack. They fight their way to Dauntless headquarters, where Tris's father sacrifices himself. Tris is attacked by the mind-controlled Tobias. Unable to kill him, Tris surrenders, which causes Four to break free of the serum's control. They shut down the Erudite simulation and free the Dauntless. They rejoin the initiates and board a train to the Amity sector to find the Abnegation survivors.
