Fans of The Dark Tower have been speculating for a while about how the movie adaptation could be reshuffling the story around a little bit. Characters were cast that don’t appear in the seven-book-long series until much later than the first installment, which hinted at some possible plot reconfiguration. A promo image of the Horn of Eld posted by Stephen King himself on his Twitter also suggested that this version of The Dark Tower might not take the same path as the one we’re familiar with. Later, director Nikolaj Arcel confirmed taking the story in a slightly different direction from the books, utilizing plot elements but moving them around a bit to make the story more movie-friendly.

In an interview with Deadline, producers Ron Howard and Brian Grazer confirmed those rumors, and talked casting that adaptation and how their version of the Gunslinger differs from that of the books. Some spoilers might follow, so only stick around if you’re into that.

According to Howard, screenwriter Akiva Goldsman came up with the idea of bringing in the Horn of Eld right off the bat. He said:

He knew it would allow us to use elements of the novels in a new combination that would give us the latitude to be true to the essence of the novels, but also re-balance and refocus the narrative in a cinematic way. That was the jumping-off point that began this process. When MRC and Modi Wiczyk became involved, that discussion deepened and we focused more on the Jake Chambers-Roland relationship at the very center of the first movie as a way of launching the universe.

In the books, it’s revealed that the Gunslinger Roland Deschain left the Horn of Eld on a battlefield long ago. At the end of the series, when Roland finally reaches the Tower, he learns that this is not the first time he’s completed this journey, and if he had had the Horn, maybe this time it would have gone differently. Instead, he’s sent back in time once again, doomed to repeat the journey over and over again until he gets it right.

Howard and Grazer also discussed finding the “hippest cast” in Idris Elba and Matthew McConaughey. Of Elba's casting, Howard said:

In this iteration, when we began thinking about candidates, Idris just felt like a really exciting and dynamic possibility. Idris brings this crucial combination of coiled danger, quiet charisma, undercurrents of complexity and nobility, and a kind of timeless cool. These are the elemental qualities of Roland, in my mind, and I think Idris carries it incredibly well.

It’ll be interesting to see how this version of The Dark Tower compares to the books, and how that translates to fans’ enjoyment of the project. By retooling the plot, this film could have the best of both worlds: giving book readers some familiarity while also providing a faster, yet still coherent, introduction for those new to the series, and maybe a happier ending overall. Don’t let go of that horn this time, Roland.

The film hits theaters on February 17, 2017.

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