VIDEO: Idris Elba Duels Matthew McConaughey in First 'Dark Tower' Trailer

The film, based on a series of Stephen King western-fantasy novels, hits theaters Aug. 4

Worlds collide in the newly released first trailer for Sony Pictures' upcoming western-fantasy epic "The Dark Tower," based on a series of Stephen King novels.

The film stars Idris Elba ("The Jungle Book") as Roland, the Gunslinger—a pistol-wielding cowboy from a ruined world. After Roland meets Jake (Tom Taylor), a boy from Earth with visions of the Gunslinger and his nemesis, the Man in Black (played by recent Stern Show guest Matthew McConaughey), the two must join together to prevent him from destroying both their worlds.

To promote the trailer, Elba and McConaughey even brought their impending showdown over to Twitter:

Directed by Nikolaj Arcel, "The Dark Tower" is billed as more of a continuation of King's eight-novel series rather than a direct adaptation. Either way, it's something fans of the material have been anticipating for decades.

"The Dark Tower" hits theaters Aug. 4. Check out Elba and McConaughey's entire Twitter exchange here.

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