The Exorcist is one of the most iconic horror movies of all time. Fans of the horror genre would be remiss if they didn't watch the film at least once. Even though nowadays we're used to horror movies containing ridiculous premises, The Exorcist contained a remarkably logical story.

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After trying every practical method possible to figure out what is wrong with her daughter, Chris MacNeil eventually turns to an exorcism. It's as straightforward a plot as that. However, while watching this harrowing tale, there are some parts of the story that might not have been clear. Read on if you want to know what the original book by William Peter Blatty made clearer than the films.

That Opening Scene In The Desert

For many moviegoers, that initial scene where Father Merrin is at an archaeological dig in the desert might have been confusing. What was with that ominous moment at the site with the eerie music, strange artifact, and immense shadows? If you didn't read the book, that moment serves as a huge disconnect from the rest of the film. In the book, it serves as an omen for Father Merrin. While picking up the demonic artifact, Merrin gets the sense that some deep and impending doom will be upon him, and as the end of the movie shows, he was right.

The Extent Of Karras' Guilt And Doubt

The movie is pretty blatant about the fact that Father Karras is going through a crisis of faith. However, the book goes far more in-depth as to why this is happening. Karras loves his mother, but due to a lack of funds and time, he can't visit her regularly. She ends up dying alone with no one around to help her. The landlord of the building ended up finding her body and reporting it. This fact, understandably so, haunts Karras during the exorcism.

Regan's Intentions When Walking Backwards

Regan's spider walk from The Exorcist

Everyone remembers that creepy scene where Regan scuttles down the stairs on her hands and feet, belly in the air and back arched unnaturally. In the movie, it just serves as another terrifying example that something is wrong with Regan.

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In the book, the scene is a little more drawn out. Regan pretends to be a snake, hissing and snapping at the ankles of the adults around her. There's something about Blatty's writing that makes this moment sound worse than it was in the movie.

Chris' Desperation

Audiences sympathize with Regan's mom, Chris MacNeil, throughout the entirety of The Exorcist. She's going through a tough time, and no one seems able to help her. She took Regan to so many doctors, and they couldn't point out what was wrong. The movie does an admirable job conveying her desperation, but only the book can truly tell the passage of time. Regan had been experiencing the effects of her possession for months. No wonder Chris was at her wits' end.

The Smoking Accent

Regan MacNeil from The Exorcist

If we're being one hundred percent honest, the significance of this particular moment flew right over our heads. Chris' friend Burke dies outside of her home one night, and it's believed that he was murdered. Later, when Regan is jamming a certain object in a certain place, she utters in a thick, British-accent, "You know what she did?"

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The book makes clear that it was with Burke's voice she spoke, which implies that the Regan demon is responsible for Burke's death. In the movie, well, we were a tad distracted by the horror to figure out what this moment meant.

Kinderman's Full Relation With Karras

Movies don't have enough time to get into the details that a book does. In Blatty's novel, more time is spent describing Detective Kinderman's personality and his slight friendship with Karras. They are both huge movie fans, and Kinderman in particular is a cinephile of the highest order. They spend a while talking about these sorts of things, which makes it sadder when Kinderman finds out what happened to Father Karras.

The Demon's True Threat To Regan

Exorcism from The Exorcist

Aside from causing gargantuan amounts of mischief, the demon's purpose in The Exorcist is not always clear. Is it just around to cause evil? Did it want to corrupt Regan? The book heavily implies that the demon's ultimate purpose is to end Regan's life. It tries to do this by keeping her awake, not letting her get a decent night's sleep. If a human body goes without sleep for a while, death is the eventual result. As such, the priests were truly fighting for Regan's life as well as her soul.

Karras Finding His Faith Again

Father Karras exorcist

The first book (as well as the first movie, we suppose) end rather happily. Regan is saved, and the demon is gone, courtesy of Father Karras inviting the demon into his own body and then tossing himself out the window. However, the ending in the book is happy in regards to matters of faith as well. Throughout the whole book, Karras was going through a crisis of faith. Doubt plagued his every step. But in his last moments, after sacrificing himself to save Regan, Father Karras regained his faith just before he died.

The Demon's Displeasure With Father Merrin

Father Merrin holds a bible in The Exorcist

The film leaves a lot to interpretation when it comes to Father Merrin's passing. Logically speaking, Merrin succumbed to ailments of the body during a strenuous exorcism. However, fans often speculated whether or not the demon had a hand in Merrin's death. The book clears up the subject a lot. It confirms that Merrin died of a heart condition he was suffering from. As a matter of fact, the demon was mightily displeased that Merrin died in that manner. It viewed his passing as the ultimate form of quitting.

Karras' Body Didn't Die

Iconic Exorcist image

For the few who have read Blatty's sequel to The Exorcist, or watched the third film in the series, they know that Father's Karras' body did not pass away after that "fatal" leap through the window. Blatty's sequel, titled Legion, reveals that the demon arranged for a serial killer's soul to be placed in Karras' body just as Karras' soul fled it. It was a strange form of revenge on the demon's part. Detective Kinderman has to solve this mystery on his own in Legion.

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