The big joke in 22 Jump Street, therefore, is that it is a sequel, and therefore you have to just do everything again, exactly the same way, only this time one door down the street and in college, rather then high school. It feels like a clever attempt to get the films excuses in early, and is slightly overlaboured at a couple of points, but also sets up the idea that the film is in on the joke, asking you to laugh along with it and not take anything it does or says terribly seriously. Which is exactly the right thing to do, because as long as you don't take it terribly seriously, its a lot of fun.
The story, of course, is the same as last time. After the success of the undercover operation in 21 Jump Street, the Police Department has approved a bigger budget on the condition that our heroes (Channing Tatum and Jonah Hill) go undercover at college to bust a drug ring. Y'know, like last time. With that out of the way, the film plumps for a rom-com narrative, rather than a buddy-movie narrative, playing the ups and downs of Tatum and Hill's "partnership" like a love story, complete with jealousy, infidelity and ultimate reconciliation. There is even a running gag about them mistaken for an actual couple, which, surprisingly and refreshingly, they manage to play off without resorting to crass "gay fear" jokes.
The supporting cast largely revolves around this central dynamic, so largely serve to line up for decent gags, or throw back on Tatum and Hill's differences. Everyone is pretty good, but a couple of the subplots get lost in the mix; especially Hill's relationship with a college Art student, which was a shame and it had the potential to be both funnier, and sweeter, than it ultimately turned out to be. Similarly there never felt like there was a lot of peril the "being at collage, wanting to find out who you are" plot for Tatum, because again it was little undercooked. The finale also comes a little out of nowhere, with a nagging doubt that maybe everyone just fancied a couple of weeks filming in Mexico.
That all sounds a little critical but the important thing is that gag to gag its pretty funny. There is some properly top-notch sequences that involve Ice Cube, who makes a great attempt to steal every scene he's in, and both Hill and Tatum shine as versatile and charming comedians. Its a safe bet of a movie, in many ways, just clever enough to be a little different without really scaring the horses by taking too many chances in what it's trying to do. It never gets baggy, and never overstays its welcome, and I laughed pretty much all the way though it, especially at the end credits, which really let rip at the "we're doing a sequel" nature of the film.