In a futuristic dystopian Chicago, society is divided into five factions: Abnegation (the selfless), Amity (the peaceful), Candor (the honest), Dauntless (the brave), and Erudite (the intellectual). The remaining population are the Factionless, who have no status or privilege in this society. When children reach the age of 16, they undergo a serum-induced psychological aptitude test which indicates their best-suited faction, though they are allowed to choose any faction as their permanent group at the subsequent Choosing Ceremony.
Beatrice Prior (Shailene Woodley) was born into Abnegation, which runs the government. Her father, Andrew Prior (Tony Goldwyn), serves on the ruling council along with the head of Abnegation, Marcus Eaton (Ray Stevenson). Beatrice takes her test with a Dauntless woman named Tori Wu (Maggie Q) as her proctor. Her results show equal attributes of multiple factions, meaning she is Divergent. Her divergence includes Abnegation, Erudite, and Dauntless. Tori records her results as Abnegation and warns her to keep the true result a secret, saying that because Divergents can think independently the government cannot control them and they are considered threats to the existing social order.
The next day at the Choosing Ceremony, Beatrice’s brother Caleb Prior (Ansel Elgort) chooses Erudite, while after some hesitation, Beatrice chooses Dauntless. After the ceremony, Beatrice meets Christina (Zoë Kravitz), Al (Christian Madsen), and Will (Ben Lloyd-Hughes), three other initiates from other factions who also chose Dauntless. Christina and Al are from Candor, and Will is from Erudite. The initiates’ commitment and fearlessness are immediately tested, and Eric Coulter (Jai Courtney), a brutal Dauntless leader, makes it clear that anyone not meeting Dauntless’ high expectations will be expelled from the faction to become Factionless. Beatrice is the first to volunteer for a leap of faith from a tall building into a dark hole, landing in a net. When Four (Theo James), a transfer initiates’ instructor, asks her name, she decides to shorten it to “Tris” so she can leave her earlier identity behind.
Tris initially struggles in Dauntless training, ranking far below the cutoff after the first evaluation, but with Four’s help slowly improves. Eric matches her against her nemesis — Peter (Miles Teller) in a fight. Tris is soundly defeated and ends up in the infirmary. When she discovers that she will miss the most important test, Capture The Flag, she leaves the infirmary and joins the other initiates, secures her team’s victory, and makes the final cut.
In the next phase of training, the initiates are subject to psychological simulations where they face their worst fears. Tris’ divergence allows her to excel at the tests, solving them in unusual ways, but Four warns her to hide her abilities and solve the challenges as a normal Dauntless would. Divergents can also manipulate tests and serums.
Tris visits Caleb, who tells her that Erudite is planning to overthrow Abnegation and become the ruling faction. On her return to Dauntless headquarters, Tris is attacked by Al, Peter, and Drew before being rescued by Four. The next day Al pleads with Tris for her forgiveness but she refuses, calling him a coward. He later kills himself by jumping into “The Chasm” rather than live with the shame.
To prepare her for the final test, Four takes Tris into his own fear simulations, where she learns that his real name is Tobias Eaton, the son of Marcus Eaton. After the simulation, they kiss. Tris then passes her test and is officially initiated into Dauntless. The rest of the Dauntless are injected with a serum supplied by Erudite which is supposedly for tracking, but is actually for mind control.
The next morning, the Dauntless prepare to execute Abnegations by the orders of the Erudites. Divergents are unaffected by the new serum, so Tris must blend in to avoid suspicion. She finds Four, who reveals himself as a Divergent. While the Dauntless move to raid Abnegation, Tris and Four separate from the group and attempt to locate Tris’ parents, but Eric realises Four is not under control and captures the two. Four is taken into custody while Tris is ordered to be executed. Her mother Natalie (Ashley Judd) appears and saves her but is shot and killed as they try to escape.
Tris finds her father in hiding with Caleb, Marcus, and several Abnegations. The group sneaks into Dauntless headquarters, where Tris encounters Peter and forces him to lead them to Erudite’s control center. Her father sacrifices himself in a shootout, and Tris goes in alone to find Four, who is now under stronger mind control designed for Divergents and attacks her. Using her knowledge of his fears, she manages to wake him from the mind control and the two enter the central control room, where Erudite leader Jeanine (Kate Winslet) is about to have the Dauntless army execute the entire Abnegation faction. Tris uses a sample of the mind control serum on her to force her to cancel the program. The group escapes the compound and boards a train out of the complex.