Amidst a world riven with old tensions, a seven-year-old boy named Aleks finds himself abandoned in the Hyperion Cloud Forest-an otherworldly place where fog could persist for days, where the displaced hide in its depths, and where whispered tales speak of a child-taking monster. Along his journey, Aleks meets other children, each with a story of how they came to the forest, and together they leave the troubled west behind. Yet misfortune shadows their path, and the east holds uncertainties of its own. As the days pass, their numbers begin to fall away, and a troubling question rises among them: Are the missing leaving of their own free will, or is there truly a creature lurking and waiting for the perfect opportunity to strike?