For three quarters of its running time, this is a genuinely funny anarchic comedy about bad behavior. It's not frivolous either. Underneath the alcohol and heroin and parties and puking there is an actual undercurrent of psychological perception. The scenes between Russell Brand and his father, played by Colm Meany, are pretty angry and bleak, while at the same time being part of the greatest scene in the movie, the furry wall party. Russell Brand (and I was not sure I could stand an entire movie about him) was great, very funny while never seeming to mug for the camera. But the movie was stolen by Sean "P. Diddy" Combs as Sergio, the president of the record company. He had some serious comedic chops.
The movie turns maudlin toward the end, and it doesn't work at all. The sentimentality seems forced and unreal. I think it was a missed opportunity on the part of the filmmakers who could have done something much much better. I didn't expect brilliance along the lines of Richard Grant's Hamlet soliloquy to the wolves in the zoo at the end of Withnail and I but maybe something that approached that.
The picture is of Elisabeth Moss, who was incredibly natural as Jonah Hill's overworked medical student girlfriend. It wasn't the greatest role (mature girlfriend of immature guy) but she was very good.