The television program 21 Jump Street is remembered, when it is remembered at all, as the show that was a launching pad for Johnny Depp's legendary career. However, that doesn't mean it is remembered fondly. It's just a pop culture footnote of the 1980s, neither lampooned or revered. As such, using it as a jumping off point for a movie in 2012 seems a bit odd, and turning a drama into a goofy comedy seems even stranger. Until you realize it actually makes more sense to do it that way than to do it in any other fashion. Especially when the movie stars Jonah Hill and Channing Tatum.
The movie only really borrows the premise of the TV show in the vaguest sense, and then just uses it as a topic for jokes. The show was about youthful cops pretending to be high school students to solve crimes and stuff. Now, suppose those cops were played by Hill and Tatum, and then suppose that they aren't very good cops. On top of that, suppose that Hill and, in particular, Tatum, can't pass for a high school senior, and that the movie is willing to use that as a joke. That's the 21 Jump Street movie in a nutshell.
Hill is Morton Schmidt. He's smart, but he lacks physical prowess. Tatum is Greg Jenko. Guess what, he's the opposite. They went to high school together, where Schmidt missed was not cool and missed the prom as such. Jenko was popular but missed the prom because his grades were awful. They meet at the police academy (sadly, there were no appearances from the likes of Michael Winslow and Wayne Gretzky's wife) and become friends. Then, because of their failures on their already limited beat, they end up at 21 Jump Street, where Ice Cube is their boss and yells at them. Their job is to find out who is supplying and dealing a new dangerous designer drug.
The rest of the movie involves Schmidt and Jenko, now pretending to be brothers, dealing with being back in high school. The film makes the choice of having their roles mixed up, so Schmidt ends up with the popular kids while Jenko is stuck in advanced classes. Do you think they learn things? They sort of do. That's the one thing that struck me as somewhat odd about 21 Jump Street. It's very silly and anarchic and meta, but they try and stick some emotional stuff in there as well. There is some hugging and some learning. It isn't a drain on the movie, but it feels somewhat odd. Giving Schmidt a sort of love interest in Brie Larson's Molly, who is a child, doesn't help, mostly because, unlike with everything else, they didn't call it out for what it is.
21 Jump Street is an action comedy in the vein of Pineapple Express, but the latter does the comedy and the action better. Which isn't to say Jump Street doesn't have good action. It is just as interested in messing with people's action movie expectations for laughs. Like I said, this is a movie that winks at the audience and is definitely commenting on itself. They play a portion of an NWA some where Ice Cube is rapping, in a movie where Ice Cube acts! It's a raunchy comedy, to be sure, but it isn't over the top with its raunch.
The movie has some strong performances. Hill and Tatum are both good, while James Franco's brother Dave Franco is impressive. Rob Riggle is also excellent in his role, providing tremendous energy to the film. Plus, the movie has three of my favorite television actors in it: Jake Johnson, Ellie Kemper, and Nick Offerman. There's also some funny cameos.
If the idea of a silly action-comedy wherein one of the characters is clearly implausibly too old to ever pass for a high school student appeals to you, then you might as well check out 21 Jump Street. You don't have to have seen the show. It has nothing to do with it. It could be a generic movie about two cops going undercover in a high school, like a cop version of Never Been Kissed. The 21 Jump Street name just gives them a few more jokes. It's a meta comedy, but its not breaking the fourth wall. They throw a lot of jokes out there, many of them scatological in nature, but most of them hit. It's a light comedy with gunplay and explosions. It's exactly what you would expect. If that's the kind of think you like, 21 Jump Street will provide you with a good, funny movie.