The Dark Tower director Nikolaj Arcel is assuring fans that a TV spin-off is still very much in the works.

The long-awaited adaptation of Stephen King's fantasy book series is a unique project in that it will begin with a feature film, followed by a prequel series designed to fill in the gaps.

Arcel recently told IndieWire that he's been heavily involved in the pilot of The Dark Tower show, which he insists is "totally canon" with his movie.

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Bear Grylls//Digital Spy

"I was part of writing the pilot, like the first season ideas and the pilot and the second episode. It's gonna be awesome," the filmmaker explained.

"What was exciting about that, whereas with the film, we were really trying to create an introduction and make a standalone film that could sort of live in itself, but what was also exciting, working on the TV show at the same time, is that is totally canon."

Arcel went on to say: "We're going back in the past. It's very, very closely adhering to [King's fourth novel] Wizard and Glass and parts of The Gunslinger novel.

"That was exciting to be even more like, 'Okay, now we're going to be able to even lift lines directly, or like [write] characters exactly as they are'. Which, as a fan, was exciting in a different way."

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Bear Grylls//Digital Spy

Last autumn, it was confirmed that Idris Elba had agreed to reprise his role as Roland Deschain (aka The Gunslinger) in the spin-off show. Young star Tom Taylor is expected to return to play Jake Chambers, too.

The Dark Tower opens on August 18 in the UK, two weeks on from its US release on August 4. Watch a trailer below:

preview for The Dark Tower - trailer 2

From: Digital Spy