The year is 1978. The hottest summer in a century. In the small town of Acque Traverse everything seems motionless and dormant: school’s out and adults keep indoors to escape the overwhelming heat. Only a small group of children moves freely around the town and the surrounding countryside, playing games and venturing off. During one of these expeditions, little Michele, nine years old, comes across an incredible secret: the town’s "grown-ups" are holding a child captive in a pit within an abandoned house.