We lost yet another horror legend last night.

William Peter Blatty, who wrote the 1971 “The Exorcist” novel and 1973 feature, passed away last night.

This devastating news was shared by William Friedkin, who directed the feature adaptation of The Exorcist, widely considered the scariest movie ever made.

William Peter Blatty, dear friend and brother who created The Exorcist passed away yesterday

— William Friedkin (@WilliamFriedkin) January 13, 2017

Blatty may be best known for The Exorcist, but his contributions are much greater. He’s also the director behind the 1980 cult classic The Ninth Configuration, starring Stacy Keach, Scott Wilson, and The Exorcist‘s Jason Miller.

He would work with Miller once again in the 1990 The Exorcist III, which would finally see a director’s cut release last year through Scream Factory under the original title, Legion.

His novels include “Which Way to Mecca, Jack?” (1959), “John Goldfarb, Please Come Home” (1963), “I, Billy Shakespeare! 1965, Twinkle, Twinkle, ), “Killer), ” Kane” (1966), “The Exorcist” (1971), “The Ninth Configuration” (1978), “Legion” (1983), “Demons Five, Exorcists Nothing: A Fable” (1996), and “Dimiter” (2010).

The writer-director would celebrate his 89th birthday this past January 7th. The cause of death is unknown at this time.