Tris's brother goes missing and later discovered dead but when things didn't add up Tris started to investigate . Upon investigating she stumbled upon a door that sent her back in time two months. While she is in the past she has to investigate what happen leading up to her brothers disappearance and so called death. Tris made a promise to her brother and she plans on keeping it but she didn't expect what will happen next. Could she save him? What really happened to him or is he really dead?