Well, it's nice to know that the totally misbegotten sequel to a big studio hit has a long tradition behind it. This movie is pretty much a failure on every level except as camp. How does a mega-million-dollar corporation let something like this happen? But if not for bizarre studio choices we wouldn't have Citizen Kane or Inglourious Basterds either, so anyways.
Anyway, while it's a dismal failure as a horror movie, there are some nice redeeming facets. John Boorman is a stronger visual stylist than William Friedkin ever wanted to be, and there are some great images in this movie, from climbing the mountains of Ethiopia to some ridiculous cliff-top monastery to buzzing around on locust-cam (which is awesome) to a weirdly trippy telepathic encounter with the demon Pazuzu in Louise Fletcher's head. And of course, Ennio Morricone does the score, so the movie has that going for it. And John Boorman is definitely more of an outside-the-box thinker than Friedkin or William Peter Blatty, with a more expansive visual and spiritual sense than either of those filmmakers.
But all the visual virtuosity in the world means neither jack nor shit when your story is incomprehensible and dopey. So otherwise, this is the one where Louise Fletcher has a box with flashing lights that allows people to enter each others' thoughts, where a tired-looking Richard Burton hams it up when he's not sitting motionless (there's a nine-minute scene where Burton just sits and watches other characters do things without saying a line or even having a facial reaction), where Linda Blair finds herelf tap-dancing in the middle of the movie for some reason, and where this happens:
(hat tip to Christian Divine.)
And I still don't know which character is supposed to be The Heretic - Blair? Burton? Von Sydow? Pazuzu? Chief? McCloud?