"There is a chasm between us, a gaping schism that only seems to widen as hard as we try to close the distance. Someday, our combined efforts to reach each other again will lead us both into the abyss."
After an overthrow of the unwanted factionless government, the war in Chicago is over. To maintain stability, the faction leaders decide to return to the faction system. Because of this, the sixteen-year-olds that chose that year are sent back to their former factions for nine months.
Tris falls into a state of depression after the war and her impromptu breakup that occurred at the end of it, and returning back to Abnegation--to the same house as her traitor brother--doesn't help.
Tobias remains in Dauntless, but while he isn't exactly despondent, he does feel out of place. He doesn't fit in and cannot go on with normal life after everything that happened.
Then, Choosing Day arrives.
And history definitely does not repeat itself when Tris goes through the initiation process with her old friends and enemies, her ex-boyfriend, and the new sixteen-year-olds, while citizens of Chicago are mysteriously dying.
WARNING: This story contains discussion of suicide and self-harm, swearing, and suggestive themes.