After a devastating plague, introverted 17-year-old Dani Campbell and her family find themselves living in a very different America, one run by a cult-like leader, who forces children to move to "safety camps" designed to protect the human race. Encouraged to flee by her parents, Dani and her five-year-old brother seek refuge in the Black Hills of South Dakota. On the run with danger around every corner, Dani must fight to ensure their survival in this new world while trying to unmask the mystery of how it all came to be.