Even the most outrageous comedy has to have some grounding in reality, if only through taking place in a world that is consistently imagined. If we don't know where we are, there may be jokes, but it is not truly comedy.
Writer/directors Jon Lucas and Scott Moore are not people with a lot of ideas. Their "21 and Over" was pretty much the same movie as their "Hangover." And the big innovation here is that this time it's girls-gone-wild instead of boys. But it plays like it was inspired by a...