Jon Lucas and Scott Moore, the rookie directors of “21 and Over,” really, really want you to know that they also wrote “The Hangover.” If you dug seeing 30-something guys spend a night or so spiraling out of control, you’ll definitely go for the just-turned-legal version, right? Well, the question is less rhetorical than they might think. Among the ingredients “21” is missing: the infectiously random silliness of a Zach Galifianakis, the smug hunkiness of a Bradley Cooper, and any sort of Vegas-y gloss whatsoever.

I’m not a “Hangover” hater, exactly, but I’ve never understood all the fuss — which makes it harder still to see the appeal of a movie that aspires to be the unplugged, raunchier, more youthquaking version. Is there endless rip-roarin’ hilarity in drinking-game montages, or tampon gags, or — in this one’s idea of a beauty shot — footage of a college kid projectile-vomiting as he rides a mechanical bull? You might have to check with someone else — if not someone who’s 21 himself, then maybe someone who’s drunk.