Miles Teller, Justin Chon and Skylar Astin play best friends who have a night that’s impossible to remember in "21 and Over." (John Johnson/Twenty One and Over Productions, Inc.)

“21 and Over” is basically “The Hangover” but younger. The first-time directing duo of Scott Moore and Jon Lucas penned both scripts, which explains their urge to recapture the success of that earlier blockbuster. But how can a couple of screenwriters outdo the scenario of inebriated friends stealing Mike Tyson’s pet tiger?

Moore and Lucas try mightily, if sloppily, while essentially painting by numbers.

Here, the cause for partying is the 21st birthday of Jeff Chang (Justin Chon). His best friends from childhood surprise him at college with a plan for debauchery. The only kink is that Jeff has — no, not a wedding — a med school interview the following morning and doesn’t want to incur the wrath of his domineering father by showing up with the shakes. Fast-talking aspiring alcoholic Miller (Miles Teller), however, won’t take no for an answer. And while the far more reasonable Casey (Skylar Astin) senses danger, he goes along for the ride.

Somewhere between that first beer and Jeff’s 7 a.m. appointment with Dad, countless outlandish misadventures unfold. A dart hits its bull’s-eye on an angry barbarian’s cheek, a runaway buffalo tramples a crowd and one series of events leaves Miller and Casey naked — with the exception of well-placed tube socks — and branded with Greek letters. The movie gets the dubious honor of containing one of filmmaking’s most artful vomiting scenes, when Jeff spews the contents of his stomach in slo-mo while riding a mechanical bull.

The dialogue and sight gags can be hilarious, which makes the writers’ insistence on racist jokes and mindless raunch all the more dismal. But despite an overload of plot points and some seriously base material, the actors seem like three young talents to watch. It says something that Teller can infuse his idiotic bully of a character with some heart.

Amid the quarters and keg stands, the movie actually tackles a deeper message about finding one’s true self and the sometimes unfortunate reality of lifelong friendships. The result is a jampacked agenda with so much going on that little is done well.

21 and Over

(93 minutes at area theaters) is rated R for crude language, nudity, sexual situations, drugs, drinking and some squirm-inducing bodily harm.