Disney+'s new movie Timmy Failure: Mistakes Were Made is a perfectly childish film, with the direction, script and cast combining to bring an imaginative sense of wonder.

Directed by Tom McCarthy (Spotlight), the comedy-drama fantasy centers around Timmy Failure (Winslow Fegley), a 10-year-old boy who lives in Portland with his single mother, Patty (Ophelia Lovibond). A stern but melodramatic child, Timmy has dedicated himself (and his partner and imaginary friend, Total, a clumsy polar bear) to protecting the city as a private detective. But while he's committed to solving the various imaginative "cases" he picks up, he's decidedly flaky when it comes to the rest of his life.

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He's at risk of being suspended from school by his teacher, Mr. Crocus (Wallace Shawn), and convinced his classmate, Corrina (Ai-Chan Carrier), is a Russian agent. He's also unconcerned about the worries of his guidance counselor, Mr. Jenkins (Craig Robinson), and his friend Rollo (Kei), or about the obvious crush, Molly (Chloe Coleman), has on him. He's especially not prepared for his mother to start dating Crispin (Kyle Bornheimer), a kindly parking enforcement officer. When his mother's Segway goes missing, Timmy's attempts to find it take him across Portland and through a mess of trouble.

The story is told exclusively through Timmy's eyes, and the film often takes flights of fancy with him whenever his imagination runs wild in quick asides. At its best moments, the movie feels like the closest thing we'll ever get to a live-action Calvin and Hobbes. It gives the main character a deceptively serious tone, which plays incredibly well off the rest of the characters around him. The world isn't sure what to make of Timmy, but is never needlessly cruel about it.

The film smartly focuses less on Timmy as a precocious child prodigy and more as an accidental screw-up who keeps making things worse for himself. This solidifies him as a character instead of making him cute for the sake of cute, an approach that could describe the whole film. The script, co-written by McCarthy and Stephan Pastis, is able to subtly tease out some major emotional beats without hitting the audience over the head with them.

McCarthy finds the perfect tonal balance, maintaining the charm of Timmy and his adventures while still anchoring them to the reality of the world around him. There might be cartoonish moments, and McCarthy gives the film a visual sense of humor that finds plenty of solid laughs, but the film always keeps a strong emotional core, with Timmy at the center. There are no long-winded speeches or platitudes about growing up, save for a quiet moment between Jenkins and Timmy late in the film. Instead, Timmy learns through his own mistakes. This provides plenty of fruitful contrast between Timmy and the rest of the cast, for both comedic and dramatic purposes.

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Fegley is given a difficult balancing act with Timmy that he pulls off successfully. The character has to be comically precocious, but with flashes of his genuine age bleeding through. While he's good in the comedy beats, he's most impressive during dramatic moments.

The older members of the cast adjust well to the tone of the film. They have a blast in the fantasy sequences while bringing a grounded sense of humanity to Timmy's escapades. Meanwhile, the other young actors are all fantastic. Kei and Coleman both find a lot of comedy in their characters, while Carrier has fun as the unassuming center of Timmy's imagined Russian conspiracy.

Timmy Failure: Mistakes Were Made is a ridiculously charming film, and one of the best in its genre. It isn't trying to be more than the fun and imaginative family film that it is, and that's perfectly fine when it's as well-crafted as Timmy Failure.

Timmy Failure: Mistakes Were Made, directed by Tom McCarthy, starring Winslow Fegley, Ophelia Lovibond, Wallace Shawn, Ai-Chan Carrier, Craig Robinson, Kei, Chloe Coleman and Kyle Bornheimer, is now streaming on Disney+.

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