The Divergent Series: Allegiant

When Factionless leader Evelyn Johnson appoints herself leader of the city, she expects her son Tobias (Theo James) to help her. Meanwhile, Tris' (Shailene Woodley) brother Caleb (Ansel Elgort) is sentenced to death for helping former Erudite leader, Jeanine Matthews, who killed many innocent citizens, including Caleb and Tris' parents.

Unhappy about the way the city is being run, Tris and Tobias escape into the world outside of the fence and are taken into protective custody by a mysterious agency known as the Bureau of Genetic Welfare.

While there, they discover that Divergents are people with pure blood and the rest of the population is damaged as a result of DNA mixing that occurred generations earlier in an effort to weed out unfavorable behaviors and attitudes.