The time has come for Kai and her friends to make a final stand, and as the war begins, everyone must choose a side. But with the lines between good and evil more blurred than ever, Kai has to stick with her convictions and follow her heart. Kai's first priority is to free Finn from the clutches of Tessa Raven, who has become no better than the evil she once fought against. As Kai reluctantly turns against the people she once considered her closest friends, she becomes entangled in a struggle with a mysterious new power that threatens to destroy what is left of Finn and change everything she thought she knew about the planet. Meanwhile, Charlie and Aric remain behind and help Raven breach the underground world of the Science Council. All bets are off as they prepare to cross every line and burn every bridge in an attempt to claim the world that has abused them for too long.