On a blistery autumn morning Rosa Hartung returns to her job as Minister for Social Affairs, a year after the dramatic disappearance of her 12-year-old daughter. Linus Berger, a mentally disturbed young man, confessed to her killing, but claims he can't remember where he buried her dismembered corpse. That same day Rosa returns to Parliament, a young mother is found murdered at her home in the suburbs of Copenhagen - she's been tortured, and one hand has been cut off. Detectives Thulin and Hess, sent to investigate the crime, arrive to find a figure made of chestnut hanging from a nearby playhouse. When yet another woman is murdered, and another chestnut figure is found, Thulin and Hess begin to suspect that there's a connection between the previously closed Hartung case and the new recent victims.