Nyle's life with her grandmother on their Vermont sheep farm advances rhythmically through the seasons until the night of the accident at the Cookshire nuclear power plant. Without warning, Nyle's modest world fills with protective masks, evacuations, contaminated food, disruptions, and mistrust. Nyle adjusts to the changes. As long as the fallout continues blowing to the East, Nyle, Gran, and the farm can go on. But into this uncertain haven stumble Ezra Trent and his mother, 'refugees' from th