10-year-old Helén Nilsson disappears on Easter 1989 in the small community of Hörby. It's a chilly evening and Helén will meet two classmates at the discount store a few minutes' walk from home, but the young friends never meet. Six days after the disappearance, Helén's wounded body is found, raped and strangled. Detective Commissioner Pelle Åkesson wants to work with the investigation but is abruptly rejected by her boss. When Helen's mother shows up at the police station and asks Pelle to take on the case, he promises to find Helen's killer.