Stephen King fans had gone berserk wondering when the trailer for The Dark Tower will release. Now, they are eagerly waiting for the release of the movie.

Also read: The Dark Tower: Three new TV spots reveal a lot about the Gunslinger and the Man in Black [VIDEOS]

And, you won't believe who has already watched the movie. It's the author Stephen King himself. In an interview with IGN, The Dark Tower director Nikolaj Arcel revealed the author is satisfied with the way the movie has turned out.

The director said: "After he saw the film for the first time, (King wrote to me), "This is not exactly my novel, but this is very much in the spirit and the tone. And I'm very happy".

Although The Dark Tower movie is not a direct adaptation of King's series of novels, King provided notes to Arcel during the writing of the script. "At one point he said, "I have some notes for script." And he sent us a hard copy of the script, with hand-written notes.

The Dark Tower trailer

"He was very polite and very respectful. It was always like, "Maybe Roland doesn't talk so much here"... he was just like the groundskeeper of the characters."

The official synopsis of the movie reads — Jake Chambers (Tom Taylor) is a young 11-year-old adventure seeker who discovers clues about another dimension called Mid-World. Upon following the mystery, he is spirited away to Mid-World where he encounters the lone frontiersman knight Roland Deschain (Idris Elba), who is on a quest to reach the 'Dark Tower' that resides in End-World and reach the nexus point between time and space that he hopes will save Mid-World from extinction. But with various monsters and a vicious sorcerer named Walter Padick (Matthew McConaughey) hot on their trail, the unlikely duo find that their quest may be difficult to complete.

The Dark Tower movie also features Tom Taylor as Jake Chambers, Abbey Lee as Tirana, and Fran Kranz as Pimli. Jackie Earle Haley, Katheryn Winnick, and Claudia Kiim will be seen in pivotal roles.

The movie will open in theatres on August 4, 2017.