Emily Blunt in Mary Poppins Returns.

Casting Emily Blunt as the iconic title character in Mary Poppins Returns, a sequel 54 years in the making, proves to be a stroke of genius.

Casting Lin-Manuel Miranda in the role of Jack, a character modeled after Dick Van Dyke’s Bert in the original classic … well, not so much.

Blunt plays the role with her own, sensible spin—not by any means copying what the great Julie Andrews did more than a half-century ago, but offering a practically perfect variation on the infamous nanny. Miranda sports the same cockney accent (though it’s not nearly as gloriously, wonderfully bad as Van Dyke’s) and plays a lamplighter in London instead of a chimney sweep. His part of the film feels like a giant missed opportunity, because while he can sing and dance up a storm, he isn’t funny. Van Dyke was funny.

The result is a movie that has a lot of charm, and some amazingly good sequences, with Blunt powering us through. When Miranda does a Hamilton-like rap in the middle of one of his numbers, it all feels a little off, as do many of his moments.

The movie takes place in the 1930s during the Great Depression; the two Banks children, Michael (Ben Whishaw) and Jane (Emily Mortimer), are all grown up. Michael, who has lost his wife, is raising his children alone. He’s taken a job at the bank where his dad used to work, but he’s way behind on the mortgage, so the very bank he works for is set to repossess his house. The problems have distracted him as a parent … so in flies you-know-who on a battered kite during a stormy wind.

As soon as Blunt shows up, the movie becomes fun. Blunt is a different Mary Poppins, yet she very much is Mary Poppins. And, man, can she sing and dance. This is most evident in a dance-hall sequence to the new musical number “A Cover Is Not the Book,” where she performs some nice vaudevillian dance steps alongside, yes, DANCING ANIMATED PENGUINS! Blunt sings the song with a cockney accent that puts Miranda’s to shame, and she out dances her co-stars, both animated and live. It’s moments like this that make Returns very much worthwhile.

Because the film is so good for substantial stretches of time, the strange, sloppy moments really stand out. Director Rob Marshall has made some stinkers (Into the Woods, Nine) to go along with his one, genuinely good film (Chicago). Some of the staging in his films, this one included, go from tightly choreographed and impressive to sloppy and unfocused within seconds. There are shots in this movie I’m surprised made the final cut. They look like a dress rehearsal.

For every brilliant sequence like the animated journey into a porcelain bowl (one of two scenes combining live actors and animation), there’s a baffling sequence, like one during which people get really jazzed about riding a bicycle—and there’s just too much of Miranda singing into lampposts. The whole time Miranda was on the screen, I was thinking stuff like, “Christian Bale would’ve been better in this role, because, ya know, Newsies, right?” I suggested this to my Disney partner in crime via text after the movie, and she basically told me to shut the fuck up.

While I might’ve been sitting on the fence regarding this film as it headed into the final turn, my attitude went full positive when none other than the man himself, Dick Van Dyke, all beautiful 93 years of him, showed up as a helpful banker. He not only shows up but gets on top of a desk and dances better than anybody in the movie. It’s only a few seconds but, I’m telling you now, they are some of the best seconds any 2018 film has to offer. Pure nostalgia heaven!

Mary Poppins Returns might be uneven, but lovers of the original will appreciate its honest and semi-successful attempt to recapture the Poppins magic. As for Blunt, she’s miraculous, effectively cancelling out any of the film’s shortcomings.

Mary Poppins Returns is now playing at theaters across the valley.