The voice of the Exorcist demon ate raw eggs, chain-smoked, and had herself tied to a chair during recordings. Mercedes McCambridge fully committed to her role as Pazuzu’s voice in the 70’s horror classic, The Exorcist. Before recording her vocals, she chugged raw eggs, chain-smoked and drank whiskey to make her voice harsher than normal. One of the most shocking funny facts: During the recordings, she had herself bound to a chair. After all of that dedication, she insisted not to have her voice credited in the film!