"Kai and Shay have gone their separate ways. As both teens continue to search for Kai's sister, Callie, Shay ends up at the Multiverse compound, a scientific cult in a remote area of Scotland. There Shay investigates the origins of the epidemic and a possible cure. And she discovers that her father, Dr. Alex Cross, has plans that jeopardize the lives of everyone in the community. Meanwhile, Kai helps his friend Freja evade capture--but he doesn't...