A near extinction-level event. A dead world with new rules where freedom comes with a price. Five years after a bioweapon called the XBU Virus is accidentally released from a Canadian government laboratory and eradicates 99.5 percent of the global population, survivors Astra Fallon and her best friend Jude Waverly emerge from her family's underground bunker in the rural municipality of Springfield, Manitoba, with nothing more than the will to survive. With food dwindling, they set out to find Astra's younger sister, Hope, who had been taken at the beginning of the outbreak to a government compound known as The Closure because of her possible rare immunity to the supervirus. But Astra and Jude quickly discover the compound is no longer a government-secured scientific sanctuary when they come face to face with Ayden Webb's end-of-the-world religious cult and Astra is forced to make a sacrifice she never imagined.