There are certain horror films that have acclaimed reputations that precede themselves, but it’s hard to top the visceral horror of William Friedkin’s The Exorcist. The Exorcist is one of the biggest movies to come out of the ‘70s and it’s had an undeniable influence on the future of the horror genre, especially when it comes to films focused on demonic possession. When horror films turn into such classics, there’s a level of reverence around them that makes the prospect of a subsequent franchise seem almost insulting.

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However, the horror genre is ripe with sequels and even The Exorcist wasn’t immune to a continued franchise that pushes the narrative into new directions. None of The Exorcist’s sequels can capture the haunted magic of the original, but that hasn’t stopped modern filmmakers from returning to the property. Even now, a “legacy sequel” to The Exorcist is about to go into production from Blumhouse. Horror audiences are about to experience a lot more Exorcist content, which makes it even more important to look back to the series’ past and understand its previous sequels.

5 The Exorcist Introduces Audiences To The Demonic Pazuzu As It Possesses Regan

Movies The Exorcist Demonic Possession Reagan Floats

There’s a lot of reverence that’s held for horror movies from the ‘70s and ‘80s, but 1973’s original Exorcist is still regarded as one of the best and scariest horror films of all time. Directed by William Friedkin and written by William Peter Blatty, based on his book of the same name, The Exorcist functions as a patient descent into terror. 12-year-old Regan MacNeil begins to exhibit unsettling and supernatural behavior that causes two priests with contrasting ideologies, Father Merrin and Father Karras, to get to the bottom of all of this.

Merrin and Karras go back and forth over whether Regan's ailments are purely psychological or something much more sinister, and it quickly becomes clear that it's a case of the latter. Merrin and Karras fight for the salvation of Regan's soul and only after much grueling work are they able to get the demonic entity, Pazuzu, to leave Regan's body. Unfortunately, Pazuzu takes up Father Karras as its new host, which culminates in Karras throwing himself out a window to his death but seemingly also the end of this supernatural threat. Regan goes on to live a healthy life with no memories of her possession, but there's still a darkness that hangs over the proceedings.

4 Exorcist II: The Heretic Digs Into Merrin’s Past With Pazuzu To Save Regan’s Future

A demonic tug of war plays out with Regan MacNeil in Exorcist II: The Heretic

Sequels are always a risky proposition in the horror genre, but Exorcist II: The Heretic is one of the more controversial and confusing examples of wasted potential and missed opportunities. Set nearly five years after the events of the original, Exorcist II focuses on Father Lamont's quest to investigate Father Merrin's death as a result of exorcising the demon Pazuzu out of Regan. Linda Blair returns as a teenaged Regan MacNeil, who undergoes deep hypnosis to get to the root of Pazuzu's origins. Lamont's journey into Regan's subconscious exposes him to a previous exorcism that Merrin performed years ago in Africa where he previously encountered Pazuzu.

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Lamont heads to Africa to find the survivor and learn how he was able to resist Pazuzu's powers. The film considers that possessed individuals like Regan are actually chosen individuals for the next evolution of humanity. Lamont and Regan personally take on Pazuzu and perform a precarious ritual to eliminate the locusts that Pazuzu often resembles. Seemingly successful in their efforts, Lamont becomes Regan's new guardian and the two hope to have a peaceful future ahead of themselves.

3 The Exorcist III Turns Up The Fear With An Undead Serial Killer On The Loose

Movies Exorcist 3 Nurse Jump Scare

William Peter Blatty, writer of the original Exorcist, returns to both write and direct the next entry in the series, The Exorcist III, which has gone on to gain an impressive cult following and is considered by some to be the scariest entry in the series. Set 15 years after Regan's initial possession, The Exorcist III ditches a lot of the baggage that ties down Exorcist II. The main conflict revolves around a series of murders that are eerily suspicious to the motives of a deceased serial killer, the Gemini Killer (an obvious allusion to the Zodiac Killer). William Kinderman, played by George C. Scott, headlines this investigation, which leads him to a psychiatric hospital and a seriously deranged patient.

Kinderman attempts to ascertain what's real, but the possessed patient in question resembles the deceased Father Karras. Kinderman's connection with Karras fuels the conflict in the film and it's eventually revealed that this demonic entity serves Pazuzu. This Gemini Killer demon intentionally takes the form of Karras as a sign of disrespect over Karras' exorcism of Regan. The Gemini Killer possesses different souls in the hospital, all of which engage in brutal displays of violence. Peace of mind for both Kinderman and Karras' eternal spirit comes down to one final exorcism, which leads to Karras' execution but stops the spree of murders. Kinderman is left more disenfranchised than ever over the darkness that fills the world.

2 The Exorcist: The Beginning Attempts To Detail Father Merrin’s First Exorcist & Crisis Of Faith

Movies Exorcist The Beginning Demonic Possession

There are lots of problems that can occur during the production of a movie, but it typically never helps when studios interfere and try to change the director's vision. Morgan Creek Productions was so concerned over Paul Schrader's version for an Exorcist prequel that they took the movie away from him and had Renny Harlin create a new origin story with Exorcist: The Beginning. Harlin's movie focuses on Father Merrin's first initial encounter with the demon Pazuzu back in East Africa in 1949. Merrin discovers a buried church that predates Christianity by hundreds of years, but its excavation triggers a series of supernatural activity and brutal deaths.

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The most interesting component of The Exorcist: The Beginning is that Merrin begins the film disillusioned with religion and questioning his faith. However, his convictions become stronger than ever once he witnesses the evil of Pazuzu and understands how important it is to have holy forces that can fight these demons. Merrin performs his first exorcism but leaves Africa still in shaky territory. Merrin still has many questions, but he’s recommitted to the cloth and ready for the work that he’ll have to do in Georgetown years later.

1 Dominion: Prequel To The Exorcist Is A More Psychological Look At Merrin’s First Clash With Pazuzu

Movies Dominion Prequel To The Exorcist Pazuzu Shrine

Dominion: Prequel To The Exorcist is the original Exorcist prequel that went into production by Paul Schrader, only to be taken away from him and retooled. However, after the failure of Harlin's The Exorcist: The Beginning, Morgan Creek Productions decided to allow Schrader to complete his original vision in an attempt to recoup their losses. This is a messy proposition all around, especially since the plots of these two movies are ostensibly the same, but Schrader's prequel is still the more sophisticated and atmospheric of the two prequels. Father Merrin comes to Kenya to participate in an archaeological dig that reveals an ancient underground church with sinister undertones. Horrible events begin to happen, with a disabled boy taking the brunt of this and becoming possessed by the ancient evil, Pazuzu.

Schrader creates a much more contemplative film that’s full of disturbing imagery. Merrin is haunted by acts that he committed back in World War II, which Pazuzu preys upon and tries to manipulate Merrin into changing his past. Merrin avoids temptation and is able to dismiss this evil spirit from Kenya, but it’s implied that Pazuzu is now hungry for revenge against Merrin, which makes their altercation in The Exorcist carry a lot more weight.

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