If there's ONE reason to see "Get Him To The Greek," it's to be dumbstruck by just how strong Puff Daddy's (or whatever it is now) comedy chops are. Seriously. Granted, he's doing self-parody, but it's a very particular sort that also calls for him to play a slow-burning nutcase. However you feel about him (I've never been a fan, myself) it's a remarkable turn, considering he steals whole scenes out from under professional comedians.
The movie itself is a mixed bag. It's funny, because Jonah Hill and Russell Brand are funny, but it's too schizophrenic to hold together as anything other than a series of sketches - though it tries to "excuse" this scattershot storytelling by leaning heavily on the device of Brand's Aldous Snow being an unstable drug addict.
Snow, we're expected to recall, was the "wild card" supporting player in Jason Segel's "Forgetting Sarah Marshall" - a pop-musician who was the subject of a "fan-crush" by Jonah Hill's schlubby hotel employee. "Greek" is meant to be a reprise of this chemistry, blown up to feature status. Hill is technically playing an entirely DIFFERENT character this time, but mostly for reasons of plot - otherwise it's the same idea: He's an overeager music geek with a particular appreciation for Aldous Snow, trying to rise through the ranks of junior music executive at Diddy's label. He pitches an anniversary concert to mark the public return of Snow, who's descended into a walking joke after a disasterous concept album and a bad breakup. He (Hill) ultimately gets sadled with the responsibility of shepherding the famous-erratic singer from London to L.A.
So, "Planes, Trains & Automobiles" meets "Cheech & Chong," is the idea, and there've certainly been worse ones. Oddly, what ultimately derails it is it's connection to "Sarah Marshall." It's trying hard to work as a buddy picture, which means it has to be "affecting" at times and develop Snow as a well-rounded character - which it pulls off, and Brand has an impressive range - but since Snow was concieved as a broad satire it's undercut every time we see or hear him performing one of his songs, which are obviously spoofs. Twice we're treated to sincere scenes in which Snow is "ressurected" onstage by the joy of performing and the affection of his fans, and both times the effect is blown because he's singing jokey tunes about venereal disease and British snackfood double-entendres.