In the spirit of fairness, nobody expected Stephen King to pop up in the Dark Tower movie.

He’s certainly there in the original novels. King’s psychopathically ambitious fantasy series, now condensed into a big-screen adaptation directed by Nikolaj Arcel, shows up in person to confront his characters in the series’ final book. Heroes Roland Deschain and Jake Chambers (who previously died, but also kind of didn’t, but now he’s fine, so don’t worry about it) travel to our world and save King from the real-life fatal van accident that nearly killed him in 1999. Their intervention ensures King can live on to write the Dark Tower novels, and they can continue their fictional quest to defend the Tower, the nexus of all realities.

As the culmination of a work that frequently jumped genres and storytelling modes over its two decades, seven primary books, and more than 4,200 pages, this insane narrative pretzel almost makes sense. But plugging it in at the close of a 90-minute film adaptation would feel unearned and uncalled-for. With so much material to adapt, and such a short movie, the Dark Tower series’ far-reaching fanbase knew they’d have to temper their expectations for the new take, at least within reason.

But even for a film tasked with making sense of a brain-busting, convoluted, fourth-wall-shattering epic, Arcel’s take on the material is far, far worse than it had to be. The troubles with the limp new Idris Elba/Matthew McConaughey vehicle go deeper than the elision of the colorful details that endeared the series to a few generations of readers. (Sorry, no android bears, vampires, or mentally splintered civil-rights activists to be found.) The methods by which the screenwriting brain trust of Arcel, Akiva Goldsman, Jeff Pinkner, and Anders Thomas Jensen reinterpret and compress several universes’ worth of mythology into 95 slim minutes don’t let any of the original text’s adherence to the Western, fantasy, science-fiction, and horror-literature traditions shine through. The Dark Tower is a genre movie that’s afraid of its own genres, a would-be cult classic intent on instead failing as a straight-up-the-middle blockbuster.

The script cherry-picks characters and scenes from various chapters. The Dutch Hill Mansion demon that attempts to swallow protagonist Jake Chambers comes from Book III: The Waste Lands. The shadowy demon that attacks Jake in a Mid-World forest resembles a giant version of the pincer-armed “lobstrosities” from Book II: The Drawing of the Three. But the film mostly draws from the first installment, The Gunslinger. In keeping with the title, the story revolves around Roland and his personal quest to take revenge on the ominous Man in Black. Through his perspective, the Dark Tower series’ relationship to the Western takes shape.

The film clearly modeled Roland’s design after that of a frontier-era pistol ace. Roland’s clothing and strong-silent-type routine hark back to one of King’s professed influences on the series, Clint Eastwood’s Man With No Name from Sergio Leone’s spaghetti Westerns. But the first novel’s deep, intuitive understanding of what makes Westerns work has been lost in translation.

Shifting the protagonist spotlight to Jake means losing sight of the world-weariness that comes from Roland’s rambling sojourn through the desert. The cowboy archetype’s fundamental inner conflict is the friction between the duty to protect a lawless land, and the brutal emotional cost of that duty. A lifetime of reading paperbacks has taught King this well; the opening chapters of The Gunslinger see Roland roving through a barren landscape and recalling his unfortunate stint in the town of Tull. He developed a slowly mounting attachment to the community, and even took a lover, but had to gun them all down following an impromptu demon abortion. (A lot of the books didn’t make it to the screen.) What might seem like a digression provides valuable emotional context for Roland’s pain. This primal scene makes sense to readers who are familiar with the Western genre. Like so many Western gunslingers, Roland doesn’t want to wield the power of life and death over everyone he meets, but he lives in a world that needs someone with that power — and his judgment.

The film places more of its eggs in the fantasy basket, using Jake’s perspective to refashion the story into a hero’s-journey narrative. But even then, the writing shies away from the more transportive aspects of King’s lovingly crafted universe. The man has put more thought into the outlay and cultural makeup of Mid-World and its adjacent dimensions than the film puts into anything. Within the greater arc of good and evil’s unending clash, King lays out a cult of psychics attempting to destabilize the Dark Tower, a completely original language made from bastardized Latin, a suicidally insane, artificially intelligent monorail, and pastiches paying homage to The Wizard of Oz, Harry Potter, and Star Wars, to name only a few references. His sprawling world teems with messy, often paradoxical life. The film adaptation could be seamlessly spliced in with footage from Eragon or Ender’s Game.

The Dark Tower novels are often brought up in conversations about so-called so-called “unfilmable novels,” and Arcel’s efforts won’t do much to change that perception. But I’m firm in my conviction that there’s a worthy movie or seven to be carved out of King’s gargantuan tangle of styles and genres. This should’ve been a producer’s dream, a franchise with the elasticity to be every kind of geek-bait at once, both a gritty post-apocalyptic John Ford riff in the vein of Fury Road, and a worthy successor to Lord of the Rings’ standard-bearing fantasizing. But the filmmakers chose to sand off all the edges, and leave something palatable and inoffensive. That also made the film’s success impossible. You’ve got to be at least a little weird to commit to thousands of pages that loop-de-loop through time, space, and literary heritages. It’s only fitting that a film adaptation should accept, and channel, a little of the books’ weirdness as well.