In a small Belgian village, a church catches fire. As the firefighters battle the flames, the scene of a dark spectacle is revealed before their eyes: two bodies, a man and a woman, sewn back to back and with their throats cut. Camille and Niemans, arrived on the spot, discover on the victims bracelets from a neo-pagan festival with strange rituals, perched in the mountain. Niemans finds a former colleague and friend, Audrey, who works in the Belgian PJ. Very quickly, this investigation brings the trio into the strange world of neo-pagan rites and leather tanneries.