On a clear October day, the American skies empty after hundreds of pilots refuse to fly. The pilots received disturbing, middle-of-the-night calls from their mothers, and each had a simple and urgent request: do not fly today. While the nation's military chiefs and artificial intelligence experts search for answers, a sixteen-year-old girl named Charlie on the coast of Maine watches a strange, silvery balloon drift across the water and toward her home -- a place she loathes. Her new home is ground zero for a story that begins at a naval base in Indiana during the winter of 1962, when a physicist named Martin Hazelton discovered something extraordinary -- and deadly.