The Pokémon franchise takes some crazy swings with a noir adventure that admirably commits to its universe, but might only be for hardcore Poke-fans.

When thinking about the premise of Pokémon Detective Pikachu, one can’t help but hearken back to early Internet meme culture’s greatest accomplishment – 2005’s Snakes on a Plane. Both films are fueled by that heady mix of irony and patent absurdity that seemingly wills a movie like this into existence. The idea of a theatrically-released big-budget live action adventure film starring Ryan Reynolds as a talking Pikachu who’s also a detective who wears a deerstalker is the stuff that would get laughed out of movie studio board meetings just a few years ago. And yet here we are, in the same place we were with Snakes on a Plane – a film whose elevator pitch is way funnier and more coherent than its execution. Turns out a meme does not a movie make.

To their credit, director Rob Letterman and his phalanx of co-writers do their damndest to commit to the premise. Set in a world where Pokémon have lived hand-in-hand with humanity throughout history, Detective Pikachu follows Tim Goodman (Justice Smith, The Get Down), a young man made cynical about Pokemon after his father Harry abandoned him to focus on his police career in Ryme City. You see, Ryme City is the one place where Pokémon and humans live in harmony, a sprawling metropolis created by gravely ill industrialist Howard Clifford (Bill Nighy) as a kind of Galt’s Gulch utopia for the creatures.

But when Harry goes missing in the middle of an investigation, Tim is drawn to Ryme City to collect his father’s things, only to be drawn into his dad’s case by his former Pokemon partner, a Pikachu (voiced by Reynolds) that only Tim can understand. The little guy’s lost his memories (and, most conveniently, his lightning powers), but not his zeal for justice, and he and Tim set off on the trail to find his missing father. In classic noir fashion, the trail leads them to another, bigger case — this one involving a mysterious purple gas called “R” that drives Pokemon into a frenzy when inhaled, and its possible connection to a Mewtwo long thought extinct. Along with a steely-eyed blogger (Kathryn Newton, Blockers) hoping for her big break as a reporter, Tim and Pikachu set off to solve the case.

Predictably, there’s a lot going on with Detective Pikachu – a kid-friendly tentpole about cute fuzzy monsters that’s also a Chinatown-esque detective story, and Lettermen and co. admirably commit to the premise. Production designer Nigel Phelps does a terrific job rendering the semi-Blade Runner aesthetic of Ryme City, bridging the weird worlds of human and Pokémon into a believable level of consistency. The Pokémon themselves are transmogrified into a realistic CG version as best as could be imagined; it’s weird to think of Pikachu as having fur, but it makes sense, as do the intricately-designed textures of the other creatures.

Unfortunately, because Detective Pikachu tries to do so much, a lot of it doesn’t end up holding up very well at the end. The erstwhile blending of kid-friendly magical creature antics and hard-boiled gumshoe activity makes for some fun sequences – particularly one in which Tim and Pikachu have to play good cop, bad cop with a Mr. Mime – but its pace and coherence leave a lot to be desired. The film slingshots between wildly different tones with reckless abandon, cracking wise about its caffeinated Pikachu one minute before sending its heroes into death-defying chases through claustrophobic laboratories the next. The idea seems to be that Pokémon are so versatile they can work in any different kind of movie, making Pikachu work more as a proof of concept than a single, coherent story.

That said, the commitment to the film’s varying moods is aided by some really strong, winning performances, particularly from Reynolds and Smith as the detectives at the center of this case. The two have the classic Who Framed Roger Rabbit? dynamic of cynical human straight-man and goofy animated sidekick, but Smith brings a surprising layer of nuanced charm to Tim. As for Reynolds, it’s nice to see that his voicework doesn’t just feel like a PG version of Deadpool; his Pikachu is a hyperactively principled detective, one whose own doggedness gets him into far too much trouble. The two have some really nice moments together, especially when reflecting on Tim’s strained relationship with his father, and it’s thanks to them that Pikachu holds together at all.

The supporting roles, however, have the inherent problem of being deliciously enjoyable turns in entirely different Pokémon movies. As the eagle-eyed reporter Lucy, Newton’s performance wouldn’t be out of place in the Pokémon anime; she’d have made a great Misty, but either everyone else needed to match her manic energy or she needed to tone it down to meet everyone else’s more naturalistic impulses. Then you get esteemed, sophisticated character actors like Nighy and Ken Watanabe milking their thespian dignity for all its worth; trust me, you haven’t lived until you’ve heard Nighy say the words “Pokémon” and “Mewtwo” with all the conviction of the Bard. The mishmash of tones between all these performances is entertainingly goofy if you’re in the right mood, but an interesting mess is a mess all the same.

By the time the film’s big action climax rolls around, Pokémon Detective Pikachu feels at once like a film made just for the fans and one that’s trying to please everybody. It takes the world of Pokémon just seriously enough to make adult fans feel welcomed while refusing to shy away from the inherent silliness of a world where humans capture magically powered creatures in little red balls. It’s admirable to see a movie take such big swings in concept and ambition, but the end result leaves you picking out the parts you liked in a sea of predictable twists, pinballing tonal shifts and a frustrating lack of depth to its characters. Sure, it’s a shallow kid’s movie at its heart, but Detective Pikachu clearly wants to be just a little bit more than its premise, and it doesn’t quite get there.