After months of speculation, The Dark Tower has officially locked in Idris Elba to play the Gunlinger, Roland Deschain, with Matthew McConaughey portraying the villainous Man in Black. Author Stephen King confirmed the news through his Twitter page today, including the very first line from his first book in The Dark Tower novel series, "The man in black fled across the desert and the gunslinger followed." Entertainment Weekly also spoke with the author, and The Dark Tower director Nikolaj Arcel, who confirmed that pre-production is under way, and principal photography will begin in seven weeks, with the January 13, 2017 release date still in place. Here's what the author had to say about this story's long journey from the page to the silver screen.

"The thing is, it's been a looong trip from the books to the film. When you think about it, I started these stories as a senior in college, sitting in a little sh-tty cabin beside the river in Maine, and finally this thing is actually in pre-production now. I'm delighted, and I'm a little bit surprised."

The Dark Tower movie adaptation has seen its fair share of adversity. The Dark Tower was initially set up at Universal in 2011, when Ron Howard was set to direct a trilogy of movies. The studio was also setting up two limited-run TV series set to air on NBC in between the films, before the project became too costly and was ultimately dropped. Warner Bros. was then eyeing the project, but they eventually passed, and the project appeared to be dead, when Sony Pictures picked up the rights last April. Sony will be teaming with Media Rights Capital to co-finance the movies, with a "complimentary" TV series also being planned.

Nikolaj Arcel is now directing from a script he co-wrote with Anders Thomas Jensen, Akiva Goldsman and Jeff Pinkner. Ron Howard is still attached to produce with his Imagine Entertainment partners Brian Grazer and Erica Huggins, with Jeff Pinkner serving as executive producer. Stephen King also confirmed that the movie will start out with the first novel's opening line, adding that he's been "pretty insistent about that." However, the movie will actually then shift to the middle of the story.

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""[The movie] starts in media res, in the middle of the story instead of at the beginning, which may upset some of the fans a little bit, but they'll get behind it, because it is the story."

The Dark Tower adaptation will bring Stephen King's series of seven novels to life, which follows Roland Deschain, a.k.a. The Gunslinger, who sets off on a journey to find The Dark Tower, rumored to be a portal to other worlds. Roland will be chased by the Man in Black, a.k.a. Walter Padick, described as an "ageless deceiver and sorcerer," who is also trying to find The Dark Tower to rule over all of its kingdoms. Along his journey, Roland will seek help from a junkie named Eddie, an amputee named Susannah and a young boy named Jake, to be part of his team known as a "ka-tet."

It was originally believed that The Dark Tower will be adapted from the first book, The Gunslinger, but both Stephen King and Nikolaj Arcel wouldn't confirm which books this first movie will be drawn from. The site speculates that the movie may be based on the third book in the series, 1993's The Waste Lands, where much of The Dark Tower mythology was laid out. The plot follows the ka-tet's efforts to reach out to Jake, who is from a different place, New York City, and time, which in the book was 1977 but it may be changed to modern-day. While those details haven't been confirmed, Nikolaj Arcel did speak about casting Idris Elba as Roland Deschain, who is described as a blue-eyed white man in the books.

"For me, it just clicked. He's such a formidable man. I had to go to Idris and tell him my vision for the entire journey with Roland and the ka-tet. We discussed, who is this character? What's he about? What's his quest? What's his psychology? We tried to figure out if we saw the same guy. And we absolutely had all the same ideas and thoughts. He had a unique vision for who Roland would be."

Stephen King added that he supported the casting, but he admitted that when he first started writing the books 46 years ago, he had envisioned Clint Eastwood as the Gunslinger. He added that over the years, he stopped seeing Clint Eastwood as Roland, and now it makes no difference whether the character is black or white. Director Nikolaj Arcel also added how this will change the dynamic of racial tension between Roland and Susannah, a black amputee, revealing that everything will be made clear eventually.

"Some fans are asking, understandably, 'What about the racial tension?' But as the story progresses that will be made clear, how we'll deal with all those things."

The original plan for the franchise was to create a trilogy of movies, with a TV series that aired in between movie. When Sony picked up the sprawling adaptation, the studio teamed up with Media Rights Capital to finance the TV series, but we haven't heard any updates about the series yet. Stephen King teased that a successful first movie could ignite talks for the series again, but it seems nothing is set in stone quite yet. Stephen King also dismissed the notion that he would appear as himself in later movies, stating he's "too old." While we wait for more details about this highly-anticipated adaptation, take a look at the tweets from Idris Elba, Matthew McConaughey and Stephen King below.