Seven-year-old Alex Alacoda finds himself abandoned in the Hyperion Cloud Forest, an extraordinary forest where low-level stratus clouds drift above the crowns of trees, fog could persist for days on end, and a beast that targets children is rumored to roam. One morning Alex meets Paul, another abandoned child who enjoys nothing more than scouting around and meeting new people. And miles away from them, a soon-to-be teenager named Felix leaves his orphanage for the forest, dreaming of a place that is not what he imagines. During a time of misfortune, Alex crosses paths with Felix, and later, with an admirable boy named Jack. Along their journey, the boys meet other children who agree to unite, but before long their members begin to vanish, and those who disappear leave no clue nor trail behind. Are they leaving of their own free will into a forest that is unforgiving? Or . is there truly a beast lurking and waiting for the perfect opportunity to strike?.