In this terrifying true story, something beyond comprehension is happening to housewife Anna Ecklund. Once a mild mannered churchgoer, she is now prone to bouts of violent rage with a particular anger toward religious imagery. Desperate to find a cure for Anna's disturbing behavior, her husband calls on doctors and psychiatrists to provide a diagnosis. But when no rational explanation can be found, local priest Father Riesinger teams up with Vatican investigator Father Lamont to evaluate the case. Realising that Anna is inhabited by a malevolent entity, the priests take her to a nearby Convent to perform an Exorcism. But all hell breaks loose and a brutal battle between good and evil begins.