During late 16th century Italy, the Catholic Church, threatened by the Protestants, unleashes the Inquisition. Menocchio, an old, stubborn, and self-educated miller, opposes the new order. Accused of heresy, he stands trial for his beliefs.
In a remote Icelandic town, a bereaved former police chief begins to suspect a local man of having had an affair with his late wife. Gradually, his obsession with uncovering the truth begins to take over his life, leading to dangerous consequences for both himself and his loved ones.