William Peter Blatty's death was announced earlier this morning in a tweet sent out by The Exorcist director and frequent collaborator William Friedkin. The famed screenwriter who wrote not only the screenplay for The Exorcist, but the original novel as well, was 89 years old.

William-peter-blatty-dead-excorist-author-screenwriter-4a76b64c-27e2-4498-9652-d5e4a17f1979William Peter Blatty (center) with Ellyn Burstyn and Jason Miller. Credit: Rolling Stone

Blatty first got his start writing comedy scripts for the legendary director Blake Edwards, creator of the The Pink Panther series featuring Peter Sellers. His screenplay for A Shot in The Dark, released in 1964, is truly one of the best entries in the entire series.

In 1971, Blatty retired from film for a bit to write his breakthrough novel The Exorcist. For those of you who aren't familiar, the story is about a twelve-year-old girl who is possessed by the devil, and the two priests who attempt to exorcise the demon. The massively successful novel remained on The New York Times bestseller list for 57 straight weeks, claiming the number one spot for 17 of them.

Blatty's background in film proved useful in adapting his own novel into what is now considered a truly revolutionary entry into the horror genre. In a market saturated with campy B-movies and Universal Studios monsters like Frankenstein and Dracula, he proved there was a place for the intelligent horror film. The root of much of The Exorcist's horror lies in its proximity to reality. If you're faint of heart, you may want to skip the clip we've chosen to include below.

Blatty would go on to win an Academy Award for his Exorcist screenplay, as well as Golden Globes for Best Picture and Best Writing.

RIP, William.