Mercedes McCambridge

Carlotta Mercedes Agnes McCambridge (March 16, 1916 – March 2, 2004) was an American actress of radio, stage, film, and television. Orson Welles called her "the world's greatest living radio actress". She won an Academy Award for Best Supporting Actress for her screen debut in ''All the King's Men'' (1949) and was nominated in the same category for ''Giant'' (1956). She voiced the majority of dialogue for demon Pazuzu in ''The Exorcist'' (1973). Provided by Wikipedia