The novel Divergent features a post-apocalyptic version of Chicago and follows Beatrice "Tris" Prior as she explores her identity within a society that defines its citizens by their social and personality-related affiliation with five factions, which removes the threat of anyone exercising independent will and re-threatening the population's safety. Underlying the action and dystopian focused main plot is a romantic subplot between Tris and one of her instructors in the Dauntless faction, nicknamed Four.