Veronica Roth

On the 10th anniversary of the Dark One's defeat, one of the Chosen Ones--who brought the Dark One down--dies and the remaining four discover the Dark One's ultimate goal was much bigger than they, the government or even prophecy could have foretold.

Going beyond the wall for the first time, Tris and Four escape Chicago, learn shocking new truths, and become involved in a battle that threatens all of humanity.