Love, retribution and redemption. Devastated by her husband's death from a drug overdose, Philippa, a British teacher living in Turin, Italy, tries to bring justice to the biggest drug dealer in Turin when the local police ignore her information about him. In building a home-made bomb and setting off a plan that fails miserably, her status changes from young widow to that of a criminal in custody. Young police officer Filipo descends into Philippa's life, changing her bleak outlook on existence into one in search of tranquility among corruption, as they become unlikely soul mates and lovers.

Alex Bernier (Ledger) is a member of an arcane order of priests known as Carolingians. When the head of the order dies, Alex is sent to Rome to investigate mysterious circumstances surrounding the death. The body bears strange marks on the chest which may or may not be the sign of a Sin Eater (Furmann), a renegade who offers absolution, last rites and therefore a path to heaven outside the jurisdiction of the church. Alex enlists the aid of his old comrade Father Thomas (Addy) and of a troubled artist (Sossamon) upon whom he once performed an exorcism. He soon finds himself plunged into a mystery only to find himself at the heart of it.