In 1609, in the Basque Country. Coming from a long line of healers, three sisters see their lives put in danger by the arrival in the region of judge Pierre de Lancre, a demonologist commissioned by King Henry IV. Hostile and terrified by the freedom and knowledge of the women, he will lead what will be one of the deadliest witch hunts in France. Plunged into the middle of a nightmare, the three sisters find themselves having to fight, each in their own way, to try to survive.