Warning: This article contains major spoilers for The Dark Tower book series.

The Dark Tower has finally released its first trailer for the long-anticipated adaptation of Stephen King’s most popular work. In fact, many consider The Dark Tower series to be King's best work - so bringing it to life must be a heavy burden for director Nikolaj Arcel. The series spans seven (very long) novels, and an accompanying comic book series. Within the story, there are multiple worlds featured, with varying timelines, and one entire novel even serves as a prequel to all the other events. There is also an eighth novel, "The Wind Through the Keyhole," that King released in 2012 - after proclaiming The Dark Tower as a complete series, many years before. Though the eighth book is not an integral part of the series, it sits between books four and five, chronologically.

Perhaps logic would have told Arcel to concentrate on adapting the first book; The Gunslinger, but the problem with that is twofold. First, book one ends on a (comparatively) anticlimactic note - that boils down to a conversation between The Man in Black and Roland (with a few supernatural/hallucinogenic events). At the end of it, the reader needs to pick up book two. That works well in reflective novels that can be read at a reader's own pace, but not in a movie, where the guarantee of a sequel is never certain. Secondly, there is fantastic material spread across all seven books, but also some scenes that would slow a blockbuster film down. Any director would need to sort the wheat from the chaff, as it were.

The Dark Tower, Jake's Drawings

As a result, Arcel has chosen to pull influence from all the books; though, mainly the first one, and assemble a revised version of the story. The logic behind that will be familiar, and fitting, to readers of the books.

The Horn of Eld plays a pivotal role in the books - and has been passed down through each generation of gunslingers The idea being that if the horn is blown, then reinforcements will come. Roland’s fellow gunslinger friend, Cuthbert, blew the horn during the battle of Jericho Hill, but no help came, and he was killed. Roland was supposed to take up the horn, but in his haste to escape, he left it behind.

When Roland reaches the Dark Tower in the final novel, he finds that his journey begins over again, and again, and again. Each time, the story is changed slightly according to his actions. In the books, when his story starts over, he is carrying the Horn of Eld. This means that earlier in his life, he did manage to take up the horn from Cuthbert. In the movie, images released of Idris Elba as The Gunslinger, Roland Deschain, have shown him in possession of the Horn. Therefore, then, we are to assume that The Dark Tower Movie is just another iteration of Roland’s tale, with changes happening as a result of his actions.

This gives Arcel fitting license with the subject material.

If we’re looking across all of the books, and then comparing them to what we know about the movie, based only on what we’ve been told and one Dark Tower trailer, we’re never going to list all of the differences. There are though, many huge moments missing, and many large moments that have been included ahead of schedule.

The Dark Tower

The biggest difference of all, is that The Dark Tower does not introduce Eddie Dean and Susannah Walker. In the book series, they enter during book two, ‘The Drawing of the Three.’ After Jake dies, Roland discovers he shares a telepathic connection with three New Yorkers: Jake Chambers; Eddie Dean, a drug addict trying to smuggle coke off of an airplane; and Susannah Walker, a double amputee who also suffers from split personality disorder.

All three characters eventually enter Roland’s world, powerless to keep from joining him on his quest to the Tower. Along with Oy, a talking dog (for lack of a better description), the group forms a Ka-tet; a family who are bonded through something far stronger than blood. For the movie, Eddie and Susannah’s absence would be logical if we were only following the first novel, but we’re not, so it’s something of a surprise, particularly given that they are a major factor in Roland’s story. However, Arcel and King have both said they envision introducing them in the future, should more movies be filmed.

It is not yet known whether Roland will allow Jake to die, as he does in the first book. Maybe, given that this is another iteration of the story, he will save him - this time. Hearing Jake utter “Go, then, there are other worlds than these” will be heartbreaking to watch on screen - so let’s hope it won’t happen.

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Idris Elba, The Dark Tower

Other major characters are also missing (at least from the trailer). Blaine the Mono hasn’t been mentioned, though King did release the book, ‘Charlie the Choo-Choo,’ that Jake buys in a bookstore. Then there’s the Wolves of Calla and Father Callahan, among others. Susan Delgado has been cast (Alex McGregor) but this movie is only likely to feature her briefly in flashback; as fans will know, her real moment comes in ‘Wizard and Glass,’ and that book is being adapted by Ron Howard for the Dark Tower tie-in TV series.

On the opposite side of the coin, there are many Dark Tower characters that appear in the movie, that don’t feature heavily until later in the book series, if at all. Jake’s mom, Laurie (Kathryn Winnick) appears in the movie, but doesn’t have much of a role in the books. Given that Jake plays a more central role in the movie, her appearance is likely intended to imbue Jake with a more sympathetic foundation on which to build. Tirana (Abbey Lee) doesn’t appear until the seventh book, and her role is minor; yet. Lee is listed among the main cast - and is said to have a substantial role. The trailer also showed a glimpse of a creature that doesn’t feature in the books - at least not in the form seen in the film (possibly a hint that new elements or characters have been introduced).

Certain events appear to be different as well - such as Roland visiting New York with Jake. The first time he visits the city in the book, he’s with Eddie. It will be interesting to see him navigating the Big Apple with those weapons on his hip, and a kid by his side.

Roland teaches Jake how to shoot in the Dark Tower

Finally, there’s the Easter Eggs. Strong references in the trailer were made to The Shining and IT. Within The Dark Tower books, there’s connections to Salem’s Lot and The Stand. Has Arcel dotted those Easter Eggs in for fun - or will they be more overt references as they were in the books?

While there might be a lot of differences between King’s books and The Dark Tower movie, it's clear that the film is still positioned to be a "faithful" adaptation of the novels - at least in tone and spirit: a mid-world lies in abandoned ruin, The Man in Black is still in deference to the Crimson King, Elba embodies the gunslinger depicted in the novels, and even recites the same mantra as he shoots.

Ultimately, the sci-fi/ horror mix will remain the same, and the themes of family, addiction, power and corruption will be at the forefront of everything. Where Arcel, King, and Howard take the series from there, remains to be seen!

NEXT: The Dark Tower Movie Trailer Breakdown

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