From the New York Times bestselling author, a gripping apocalyptic thriller about a paramedic who must stop billionaire survivalists and their AI from turning the end of the world into a curated opportunity for power. At the world's end, only one place is safe...and everyone is dying to get in. When the world stands on the brink of nuclear war and global tensions spiral toward catastrophe, there is a remote New Hampshire valley rumored to be a Shadow Zone, where people can take refuge from fallout and nuclear winter. Millions flood north, abandoning cities, laws, and morality in a desperate race to survive. When New York paramedic Michael Ryan finds himself in the Shadow Zone, he discovers that it's divided between newcomers seeking refuge and billionaires, who've built a luxurious, AI-powered doomsday bunker long before the apocalypse began. To them, the coming apocalypse isn't a tragedy. It's an opportunity. And the refugees outside are not meant to survive it. As violence escalates, we witness AI instigate human conflict, and we follow Ryan as he races against time to prevent the killing of hundreds of thousands of people.