The very last line of the novel—"Then the shouting begins" (47.82)—might as well read "To be continued in Allegiant, available in hardcover wherever books are sold." None of the questions Tris is trying to answer throughout the novel are explained. In fact, even more questions are raised. It's like any given season finale in Lost.
What are these questions, you ask? We've got you:
Evelyn ends up surprising everyone (read: no one who wasn't paying attention) by taking over and abolishing all the factions, something she was talking about way back in Chapter 9. What will the city be like without factions?
Tris's relationship with Tobias is in shambles. That's what happens when you lie to your boyfriend and side with his maybe-evil father. Will Tobias forgive her?
Tobias helps Marcus and Caleb by bringing in the video of Edith Prior. Why didn't he just help them in the first place? How many lives would have been spared if he had?
Who the heck is Edith Prior? She says people are waging a war against human nature itself, and the time will come for the Divergent to see what's on the other side of the fence and help save humanity. Save humanity from what?
And that's just the new stuff. Tris is even more confused about her parents' actions and even less sure of what it actually means to be Divergent. Allegiant, here we come.