Time and influence have dulled its power but still an engaging film.

Rating: 10/10 (20 August 2019)

(comments based on the director's cut)
As the best known and best received demon possession film much of the current crop of horror films owe a lot to this gem of the 70's. The Nun (2018) probably wouldn't exist without the success of this film. Many common horror tropes get worked into this story. Psychological horror being more intense than physical horror. Old age religion having problems with new age sexuality is a major theme in the story. Or how the characters ending up regaining their faith in God because of the devil. It goes as far as sound design and discordant images being used. The jump scares are plentiful here and you can see why that aspect has become a cliche in horror. This makes the film very fun to spot its influence but it also has made it less intense and less scary watching it today.
It is a minor issue because while the visceral horror is gone the wonderful atmospherics, deeply impressive effects, and engaging story remain. The direction in this film is a solid technically dazzling piece of work. The film remains creepy in large part because of the skill of Friedkin. That is not to say the film isn't well acted. It is very well acted. Surprisingly graceful and naturalistic the entire cast is undeniably intense and striking.
I think the real key to this film's success is just how long the build up to the full blown horror scenes is. Well over an hour is spent laying down story threads and characterization. It gives the eventual chills thematic and emotional weight. Such a fine piece of story conception in terms of pacing.