After years spent in development hell, the first adaptation of Stephen King's The Dark Tower epic finally made it to theaters in July. But despite the involvement of such names as Idris Elba and Matthew McConaughey, the film was met with largely negative reviews and a disappointing box office. With ambitious plans are apparently still under way for sequels and a connected television series, King himself weighed in on The Dark Tower's major stumbling block, and how how the franchise can successfully move forward.

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"The major challenge was to do a film based on a series of books that’s really long, about 3,000 pages," he told Vulture. "The other part of it was the decision to do a PG-13 feature adaptation of books that are extremely violent and deal with violent behavior in a fairly graphic way. That was something that had to be overcome, although I’ve gotta say, I thought [screenwriter] Akiva Goldsman did a terrific job in taking a central part of the book and turning it into what I thought was a pretty good movie. The TV series they’re developing now…we’ll see what happens with that. It would be like a complete reboot, so we’ll just have to see."

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King seemed to politely voice his concerns about a PG-13 adaptation right before The Dark Tower hit theaters, indicating even then that he felt the source material would require an R-rating to truly work moving forward. There's no official word about a change in plans for the series, which is supposedly still planned as a film trilogy, with television seasons airing between each entry.

Directed by Nikolaj Arcel, The Dark Tower stars Idris Elba, Matthew McConaughey, Abbey Lee, Katheryn Winnick, Fran Kranz, Claudia Kim and Jackie Earle Haley.