The men and women who created The Dark Tower made a lot of mistakes, including a few catastrophic ones, but they did one thing exactly right: They chose Idris Elba as their lead. This film will only reinforce what people who’ve followed Elba through The Wire and Luther and a lot of movies (like this one) that were unworthy of his gifts already know: He is one of the most compelling screen presences of his generation. Even when the movie around him is total garbage nonsense, it is fun to watch Idris Elba; the way he walks, the way he stares at people with eyes blazing with intensity. He is an ideal action hero. He looks like the coolest man who ever lived in his fantasy Western garb, and he moves with a rare combination of grace and force, like the best parts of Gene Kelly mixed with the best parts of Chow Yun-fat. He makes an amazing Gunslinger. Sadly, he’s trapped in a not-very-good Gunslinger movie.

It is a complicated adaptation of Stephen King’s epic fantasy series; part abridged reboot, part sequel. To a novice viewer (i.e. me), it was equally baffling and frustrating; it was never entirely clear who Elba’s Roland Deschain was or why he was important, or how he came to be trapped in this apparently endless war with the man he calls Walter, and others call the Man in Black, played by Matthew McConaughey. It’s unclear because even though Elba makes an incredibly charismatic vigilante, he’s mostly a side character in the story of a deeply uninteresting kid named Jake Chambers (Tom Taylor), who lives in New York City and suffers from recurring nightmares about Roland and the Man in Black and a mysterious tower in the sky.

Jake is convinced these dreams are real, and draws them in impressively detailed sketches he hangs on his bedroom walls. But everyone, including his concerned mother (Katheryn Winnick), thinks he’s crazy. Even Jake’s therapist insists his fear of an impending apocalypse is all made up, which seems particularly cold because the world keeps getting rocked by repeated unexplained earthquakes. There’s an earthquake during their therapy session! Maybe they shouldn’t be so quick to dismiss this kid.

Jake’s dreams are real, of course, and eventually he manages to find a portal to Roland’s home in Mid-World in Brooklyn’s Obvious Backlot neighborhood. Even though Jake is drawn from the Dark Tower books, the moment he meets Roland and starts tagging along on his trek through Mid-World, The Dark Tower begins to feel less like an adaptation of a famous novel and more like fan-fiction by someone who always wanted to hang out with the Gunslinger. Later, the film morphs into a kind of shadow remake of Last Action Hero, as Jake and Roland travel back to New York City and the gunslinger is comically baffled by things like Coca-Cola and hot dogs. (“What breed?” Roland asks as he takes a bite.)

Sony Pictures

For a movie based on one of the most beloved book series in history, the writing in The Dark Tower is sometimes shockingly bad. (The screenplay is credited to Anders Thomas Jensen, Akiva Goldsman, Jeff Pinkner, and director Nikolaj Arcel.) A lot of McConaughey’s dialogue is laughable (“Have a great apocalypse!” might be the highlight), all of it delivered with enough over-the-top gusto to bring the McConaissance to a permanent conclusion. The structure is a total mess as well; the very first scene feels like it was pulled out of the third act of another movie (one involving children strapped to torture chairs that make their brains send beams of energy into the sky). When Elba gets to do stuff with his guns, it’s really cool, but his character takes forever to show up in the movie at all, and then doesn’t fire a single bullet for 45 minutes. For half of The Dark Tower he is not technically a gunslinger. He’s just a guy wandering around in a desert with a boring kid.

The scope of King’s material would seem to demand a director of bold vision, capable of conjuring literally entire universes onscreen. Based on the evidence here, Arcel is not that director. Although The Dark Tower technically traverses multiple planes of existence, it feels like the whole movie takes place on one Western cliff, a nearby town, a futuristic set where Walter plays with some glowing balls, and a single New York City block near Union Square. There are a couple of sequences where Roland squares off with monsters or zombies or something — I sincerely don’t know what to call them because no one explains who they are, where they came from, or what they’re doing — and all of these scenes take place at night in dimly lit forests and villages and there isn’t a single clear establishing shot of any of the creatures. It’s flat-out ugly.

Sony Pictures

The Dark Tower left me confused and often very annoyed, but not necessarily bored. Part of that is because the movie has been cut to the bone; at 95 minutes, it’s always moving forward, often to its detriment. (A slower movie would have deepened the characters and brought out their motivations for members of the audience who don’t already know that stuff from the novels.) But that’s also partly because of Elba, who is one of those movie stars you can’t take your eyes off of. If this movie fails, I sincerely hope he isn’t the one who gets blamed, or that decision makers in Hollywood use it as the reason not to cast him as the lead in other blockbuster tentpoles. Surrounded by so much that doesn’t work, he is the only person present who seems to have gotten things exactly right.