In this sequel to Divergent the war between the factions is well under way; Tris is feeling overwhelming guilt because of the deaths of her parents and her friend Will; and the romance between Tris and Tobias (Four) is tested by divided loyalties.
I liked this book better than Divergent. I appreciated the more extensive explanation of the factions and the deeper development of the characters. We discover that the "good guys" and the "bad guys" are not that clear cut and that some characters are harboring unexpected secrets.
The basic thrust of the story is that Erudite is trying to take over the city and become the main governing faction. To this end Jeanine, the head of Erudite, is trying to develop a serum that gives her control of every person in the city, including the Divergents. Jeanine will do anything to accomplish this goal - manipulate, torture, kill, whatever it takes - and enlists some unexpected allies to help her.
Jeanine needs a test subject for her serums, which turns out to be Tris. In any case, there is a huge secret behind Jeanine's machinations and the revelation of this secret at the end of the story is the bridge to book three.
I thought Tris was too whiny in this book, constantly thinking of the deaths of her loved ones and wondering if she was better off dead as well. This got old. And the romance between Tris and Tobias got too icky for me with constant scenes of kissing and pressing their bodies together. It's possible, though, I would have loved these scenes when I was a teenager.
I'm planning to read book three (Allegiant) to see how the rest of the story plays out.