When Wynter Roth is turned out of New Earth, a self-contained doomsday cult on the American prairie, an outbreak of rapid early onset dementia is spreading across the nation. As Wynter finds herself face-to-face with the apocalypse she's feared all her life, her sister arrives with a set of medical samples. There's something far more sinister at play -- and these samples are key to understanding the disease. To get the samples to a lab in Colorado, Wynter takes up with former military man Chase Miller, who has his own reasons for getting close to the samples... and to Wynter herself.