If you're a true horror movie fan, you've no doubt watched The Exorcist (1973) at least a billion times. The making of the film is rife with controversy, mystery, and lore that is almost as captivating as the film itself. Watching its behind the scenes footage is like taking a class on screenwriting, directing, acting, and special effects all at once, and chances are if you've seen The Exorcist, you've probably seen The Fear of God, the documentary that accompanied the 25 Year Anniversary Edition DVD. However, here's some rare behind the scenes footage you may have not come across from the set of one of the most terrifying films ever made.

Before I get started, I have to preface this: The Exorcist is my favorite horror film of all time, and probably ranks somewhere in my top 5 overall. I grew up with it, love it, and to this day refuse to buy or look at pendulum clocks. So, I have to commit to brevity, since I could talk about it forever.

The story behind the film is rich and intriguing. Filmed mostly in Georgetown, the film saw more than its fair share of wicked and unexplainable occurrences on and off set. Nine people who were somehow connected to the film died during and after filming, including Jack MacGowran who played Burke Dennings. A mysterious fire also broke out on one of the sets.

However, intense and ingenuitive filmmaking was going on as well. Some of the more well-known stories are that director William Friedkin notoriously put his actors in harm's way in order to get the shots he wanted. Tickets were sold to Georgetown students and anyone else who wanted to sit atop the buildings surrounding the set to watch Father Karras' iconic fall down the stairs. Friedkin recalls how Mercedes McCambridge prepared for her voice performance of the Devil for the film:

She was chain smoking; swallowing raw eggs; getting me to tie her to a chair; all these painful things just to produce the sound of a demon in torment. And as she did it, the most peculiar things would happen in her throat. Double and triple sounds would emerge at once, wheezing sounds, very much akin to what you would imagine a demon in torment might sound like.

Director William Friedkin on the set of 'The Exorcist'

McCambridge also explains in an archival interview that the residual effects of her childhood affliction with bronchitis allowed her to produce that guttural demonic wheeze. (She begins talking about it at 7:40, but the whole interview is pretty interesting.)

Check out this rare footage of the work that went on behind the scenes of The Exorcist, which shows how some of the special effects worked, as well as some eerie shots of makeup artists working on the spinning Reagan head.

Thanks to Cinephilia and Beyond for sharing this video and for also mentioning that the 40th Anniversary Edition of The Exorcist for Blu-ray will be available on October 8th.

What are your thoughts on the special effects/horror/narrative/etc. in The Exorcist? Let us know in the comments.

[via Cinephilia and Beyond]