THE EXORCIST is about a mother Mrs. MacNeil (Burstyn) of a 12 year old girl named Regan (Blair) who believes there is something more to her daughter's severe dysfunctional behavior that cannot be explained by conventional means and finds herself turning to two priests for answers to her daughter's unusually bizarre behavior: one, a depressed and faithless Jesuit Father Karras (Miller); and the other, a retired Exorcist Father Lancaster Merrin (Von Sydow) who both after investigation of Regan's condition, unequivocally believe there is evidence of demonic possession by an evil spirit named Pazuzu. Their attempt to exorcise Regan (Blair) leads to one of the most shocking moments of the film that scared audiences out of their seats running for the exits and caused audiences mass hysteria when released theatrically in 1973... causing many movie goers to faint after watching the entire film to its compelling and terrifying conclusion.