Not exactly what you're asking, but I think of The Exorcist as a partially cancelled book (and it pisses me off, lol). William Blatty admitted he had to rush into the end because they were pressuring him to publish and that's why it felt WAY TOO out of place with the rest of the book. And it's such a shame, honestly, I would have loved to read the original idea for the exorcism and the ending