Mateo, a young Mexican man, embarks on a pilgrimage through Spain to confront his past, but becomes entangled in a dangerous Catholic cult where forbidden love threatens his very survival.
In the sixteenth century, Francis Barnard travels to Spain to clarify the strange circumstances of his sister's death after she had married the son of a cruel Spanish Inquisitor.
After participating in a séance, young Laura begins to behave strangely. Alarmed, her parents ask Father Olmedo, one of the few exorcists authorized by the Vatican to intervene in cases of demonic possession, for help.