Even nonfans might be familiar with the basic details of the Pokémon game through cultural osmosis. Pokémon are brightly colored elemental beasties, magical-looking lizards and birds and canines and rodents and the like, that possess specific powers; people use special devices called Pokéballs to capture them and pit them against one another in battle. Detective Pikachu throws most of that out the window—there’s not much battling going on, and our hero, Tim Goodman (played by Justice Smith), is an insurance agent who claims he outgrew his childhood dreams of Pokémon training years ago. That changes when Tim’s father, a gumshoe from the nearby metropolis Ryme City, dies in a fiery car crash. As Tim goes to settle his affairs, he runs into a wiseacre Pikachu (voiced by Ryan Reynolds) that—unlike most Pokémon, who can only say their own name—can communicate with Tim, and is convinced that the elder Goodman’s death was staged.

Together, Tim and Pikachu start to unravel a conspiracy implicating the Murdoch-esque media empire at the heart of the city, which is headed by the Pokémon lover Howard Clifford (Bill Nighy) and his weaselly son Roger (Chris Geere). Ryme City itself is a Flintstones-style conurbation where humans and Pokémon live side by side, meaning that bizarre-looking CGI creations can be seen taking drink orders or ripping subway tickets. I realize that all this sounds like the addled ravings of a Nintendo advertising executive, but Letterman and his co-screenwriters Dan Hernandez, Benji Samit, and Derek Connolly do their damnedest to make the world seem tangible. Yes, Ryme City is crowded with flame-tailed Charmanders and marshmallow-textured singing Jigglypuffs, but it feels more like an entrancing alien planet than an exaggerated, hollow branding exercise.

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Incredibly for a movie of this scale, Detective Pikachu is shot on 35-millimeter film (a departure from the digital norms of contemporary Hollywood), and the cinematographer John Mathieson lights it rather distinctively, bathing scenes in neon light and hazy filters. The pocket monsters themselves look remarkably tactile and distinctive, escaping the CGI flatness that’s typical of these kinds of creature features. Atop it all is the great detective himself, a bullish but sensitive motormouth played with Reynolds’s usual swagger but animated as a 16-inch-tall furry yellow animal of inordinate cuteness. The performance was created through motion capture of Reynolds’s face, and it shows in every furrowed brow and plaintive pout.

I have a definite fondness for the weird Nintendo characters that are being brought to life here; if you’re a disinterested neophyte, you might not get much of a thrill from seeing a place like Ryme City on-screen. Still, Detective Pikachu does have a perfectly robust plot to offer, and a nice grasp on its overall kid-friendly tone. The jokes are never too arch or edgy, nor do they rely on the cheap, tiresome physical gags that plague so many PG-rated animations. The film tries to approach its central mystery as sincerely as possible: There’s a case to be solved, and a nice young man is on it, with a grizzled, hat-wearing electric mouse in tow. No doubt most Hollywood executives are as baffled as I am that Detective Pikachu made it to the big screen. But even more baffling, and heartening, is how well it all works.

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