The faction-based society that Tris Prior once believed in is shattered, fractured by violence and power struggles and scarred by loss and betrayal. So when offered a chance to explore the world past the limits she's known, Tris is ready. Perhaps beyond the fence, she and Tobias will find a simple new life together, free from complicated lies, tangled loyalties, and painful memories. But Tris's new reality is even more alarming than the one she left...

Tris and Four are now fugitives on the run, hunted by Jeanine, the leader of the power-hungry Erudite elite. Racing against time, they must find out what Tris's family sacrificed their lives to protect, and why the Erudite leaders will do anything to stop them. Haunted by her past choices but desperate to protect the ones she loves, Tris, with Four at her side, faces one impossible challenge after another as they unlock the truth about the past and...