When "The Exorcist" was celebrating its 25th anniversary in 1998, actor Jason Miller, who played Father Damien Karras, remarked (via News & Record), "In the lexicon of movies, it's right up there as probably one of the top horror films of our time."

At the time, film critic Mark Kermode was interviewing Miller for what would become the BBC documentary, "The Fear of God: 25 Years of The Exorcist." This was before a new 2000 edition of the movie, "The Exorcist: The Version You've Never Seen," restored the infamous lost scene with the demon-possessed girl, Regan MacNeil (Linda Blair), walking backward down the stairs like a spider.

There are no shortage of shocking moments in "The Exorcist," but for Miller, one of the biggest shocks came on the set while they were filming. It's a sheer gross-out moment that also may have helped the phrase "projectile vomit" enter the lexicon of certain viewers (those who had never had the misfortune of experiencing such a thing or even hearing about it in real life before).

There's an old playground joke, the simplified version of which goes:

What did you eat all day?

Pea green soup.

What did you do all night?

Pee green soup.

It was no laughing matter, however, when Miller had pea green soup projectile-vomited onto his face during the production of "The Exorcist." As Miller (who passed away in 2001) told it, the plan was for Regan's projectile vomit to land on his chest — and that's the way it happened all throughout rehearsals. When the cameras were rolling, though, the vomit was suddenly "aimed" right at his face. And that's the take that made it into the movie.

By Accident Or Design?

The soup-to-the-face incident wasn't the only time something unexpected happened on the set of "The Exorcist." The stories of director William Friedkin's unorthodox methods for eliciting raw reactions from his actors are legendary. In the case of "The French Connection," the Academy Award-winning film he made before "The Exorcist," Friedkin actually staged an illegal car chase that he later admitted put people's lives in danger.

According to Miller, Friedkin also had shotguns going off on the "Exorcist" set to create tension. Looper notes that the guns were firing blanks, but it's understandable why just the abrupt sound of them would put the actors on edge.

An even more well-known behind-the-scenes "Exorcist" story involves Friedkin slapping a real priest right before a shot to provoke a genuine emotional response and get it on film. It was Father William O'Malley, who played Father Joseph Dyer in the film. Friedkin at least had the decency to ask, "Do you trust me?" before he did it, which is more heads-up than he gave Miller with the vomit.

Friedkin has since said that he regrets some of his extremely guerrilla filmmaking techniques in the 1970s and would not employ them today. In today's sensitive climate, it feels like those techniques wouldn't fly with anyone. Yet for better or for worse, they were woven into the fabric of his filmmaking on "The Exorcist," an old-school '70s blockbuster that had Hollywood laughing — and projectile-vomiting? — all the way to the bank.

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