Allegiant

After the city's revelation, Evelyn takes power in Chicago and forces the factions to live alongside the Factionless. The Allegiant want to restore them, and tension rises. Tris, Tobias and a few friends decide to leave the city and find out what lies beyond the wall. There they meet the Bureau of Genetic Welfare, which explains why Chicago was created and what it expects of them. Tris gains access to her mother's memories and to new versions of the truth. The narration alternates between her and Tobias, and the two disagree about what to do with what they've learned. The decision on how to end it all falls to Tris.

1. ChangeTwo narrators

   The book alternates chapters between Tris and Tobias, each narrating in first person. The film doesn't use that two-narrator structure.

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2. ChangeThe film stops halfway

   The book was split into two films. Allegiant covers only the first half, and Ascendant, which would have shown the rest, was never made.

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3. ChangeChicago after the reveal

   In the book, Evelyn becomes leader and forces the factions to live alongside the Factionless. In the film, Evelyn closes the wall again and puts Jeanine's allies on trial.

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