A new case for Olivia Rönning and Tom Stilton: A body is discovered in a large anthill in the Swedish forests. Olivia Rönning is to support the local police in the murder investigation. The dead man's head has disappeared. The victim's fingerprints are not to be found in any database, and no one has been reported missing in the area for over twenty years. The crime scene is not far from an old Sami sacrificial site, where forensic experts find clear traces of blood. Fear is spreading in the nearby village of Slagtjärn. Is it still safe to walk alone at dusk? Thanks to the influx of city dwellers and Dutch emigrants, the small town enjoys a lively atmosphere.