The Exorcist Movies: The Beginning Timeline
This chronological watch order uses Exorcist: The Beginning as the prequel, showing Father Merrin's first encounter with demonic forces in Africa.
This version was the studio's preferred cut, featuring more conventional horror elements than Dominion. While telling essentially the same prequel story as Dominion, The Beginning takes a more action-oriented approach to the material.
There are 4 other watch orders available - see the links up above.

Exorcist: The Beginning
A prequel exploring Father Merrin's first encounter with the demon Pazuzu in East Africa, years before the events of the original Exorcist film.
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The Exorcist
When a 12-year-old girl begins exhibiting disturbing supernatural behavior, her desperate mother turns to two priests who must perform an ancient exorcism to save her daughter's soul.
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Exorcist II: The Heretic
Four years after her demonic possession, Regan MacNeil is plagued by disturbing nightmares, prompting a Vatican investigator and research specialist to determine if the evil has returned.
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The Exorcist III
Fifteen years after the events of the original exorcism, Police Lieutenant Kinderman investigates a series of brutal murders that bear an unsettling resemblance to the methods of a supposedly dead serial killer.
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Other Film Series
Chernobyl
Feature films exploring the 1986 Chernobyl nuclear disaster and its lasting impact on the exclusion zone.
Invasion of the Body Snatchers
Four films exploring alien pod people replacing humans, each updating the concept for different eras and anxieties.
Romero's Living Dead
George A. Romero's groundbreaking zombie saga, featuring classic horror films and several reboots.
Silent Hill
Horror films based on the acclaimed video game franchise, exploring the nightmarish town of Silent Hill through interconnected and standalone stories.
The Conjuring Universe
Supernatural horror franchise following paranormal investigators Ed and Lorraine Warren and their haunted cases.
The Purge
A dystopian horror franchise set in an America where all crime is legal for 12 hours once a year during an annual event called The Purge.