Kylie Eaton and Cassandra Isle, best friends, grew up together in the hell that is the faction: Abnegation. They had Imogen's brother; Tobias at one point there to protect them from an abusive father, but once it turned up that he had the chance to he chose differently and left home for a completely new and opposite life to where he'd grown up, leaving behind and breaking the heart of his sister. But now the girls are both 16 and it's their turn to choose. Spoiler they will stay together, but once they both fall in love with two Dauntless trainers that are also Mortal Enemies will they truely still be together?