In a quiet suburb of Copenhagen, the police make a terrible discovery: a young woman is found brutally murdered on a playground. One of her hands is missing. Above her hangs a little man, made of chestnuts. The case is assigned to young and ambitious detective Naia Thulin and her new partner, Mark Hess. They soon discover that a puzzling piece of evidence on the male leads to a girl who went missing a year earlier, and was presumed dead: the daughter of politician Rosa Hartung.