Freyr, a doctor in a city in Iceland, assists local police when an elderly woman is found hung inside of an old church. Crosses are found carved into her back, which is assumed to be the result of abuse, but when the dead woman’s husband insists he never touched her, policewoman Dagny links the death to the mysterious disappearance of a young boy, Bernódus, who vanished decades earlier.
Dagny shows him a photograph of Bernódus’s classmates, with eight of their faces scratched out with crosses. She explains that the classmates were known for bullying Bernódus, who had crosses carved on his back from his ultra-religious, abusive father (who blamed him for the death of his wife in childbirth). Six of the eight have been killed in mysterious accidents and were all found with crosses carved into their backs. Freyr, who is still reeling from the unsolved disappearance of his own son, Benni, while Benni was playing hide-and-seek with a friend, begins to see visions of Bernódus.