The tried-and-true comedy setup of the hard-partying fraternity vs. the stuffy adults has been a staple of American films ever since the classic “National Lampoon’s Animal House.” “Old School” put a new spin on it by having middle-aged men relive their college heyday, but for the most part, it’s been diminishing returns for the genre ever since.

“Neighbors” changes the formula ever so slightly, but is a surprisingly lazy, mixed bag that relies too heavily on the likability and quick-witted charm of most of its cast.

Seth Rogen and Rose Byrne play Mac and Kelly, a newly married couple trying to raise a child and not give up their fun-loving independence. When a group of frat boys (led by Zac Efron and Dave Franco) move in next door, the joke is not that Mac and Kelly represent the establishment — like so many other fight-for-your-right-to-party movies — but that they are essentially powerless.

An early scene in “Neighbors,” directed by Nicholas Stoller (“Forgetting Sarah Marshall”) encapsulates the uncomfortable push-and-pull of the entire movie. When a friend pressures them into coming out one night, the young couple decide finally that enough is enough — just because they have a kid doesn’t mean they can’t ever go out and have fun, right? So they rush around the house getting all the things ready to “responsibly” take their toddler… to a rave. It’s fun to entertain the idea that they might momentarily think this is OK, right up until the punchline.

There’s a jump cut from all their furious running around the house to both parents — wait for it — asleep in front of the front door, pooped from getting all the diapers, breast pumps and what-not ready.

Like the rest of the movie, these temporary lapses of sanity feel like they should be more funny (or believable) more than they actually are. It’s nice to see a couple get into trouble and make terrible decisions together, though, instead of reducing Byrne to the naggy wife character that so often populates these kinds of films (hello, “Hangover”).

She and Rogen have a nice rapport as each one tries to persuade the other (and themselves) to do more and more absurd things to fight back against the partying fratties next door. She even has a scene that may hit home with some people where she tries to convince herself what fun it’s going to be to be a stay-at-home mom.

Maybe if “Neighbors” would have embraced the dark side of parenting, and really let Mac and Kelly go off the deep end like most parents sometimes wish they could, it would have been a more striking movie — and one with something to say.

Instead, the script, by Andrew J. Cohen and Brendan O’Brien, meanders around a vague revenge plot, circles a tired lesson about accepting responsibility, and eventually settles on time healing all wounds. Yeesh.

It works some of the time, mostly because of Rogen and Byrne, but as with most gross-out comedies, the shock humor seems to come out of nowhere rather than develop naturally from the scene. A certain desperate quality is to be expected from a modern comedy in this genre as it tries to one-up its raunchy forebearers, but not everybody has the comedic chops to pull it off. Zac Efron in particular is not the right guy to smooth out a sequence that already seemed forced on paper. Even when he’s playing genial, it comes off as insincere. So when the “Neighbors” inevitably get their comeuppance, it doesn’t matter one iota.

‘Stage Fright’

Opening this weekend at the Screenland Armour and on-demand/VOD outlets is “Stage Fright,” a hybrid musical-slasher film that sounds like a lot of self-aware fun in theory. Unfortunately, writer/director Jerome Sable fills his script full of so many leftover plot elements and references to other movies that it chokes the life right out of it.

Allie MacDonald is the girl at the center of a bunch of killings that are even more nonsensical than usual, at a summer camp for the performing arts that’s run by none other than Meat Loaf. Her mother (Minnie Driver) was murdered on opening night of a big Broadway play, and now the same masked killer — who warbles like Weird Al doing Christian Bale’s Batman, enunciating every word in that musical theater way over the top of ridiculous thrash metal tunes — is stalking her camp.

It’s strange to hear kids break out into song after a gruesome stabbing, and there’s a certain amount of “Glee” in watching some of the snobbier types get theirs, but “Stage Fright” is never a film that gets you involved. Instead, it holds you at a distance, poking fun at everything.

For all its references to the films of Brian De Palma (“Phantom of the Paradise,” “Carrie,” “Body Double”), it has more in common with the “Scream” franchise if anything, including a reveal of the killer that’s ho-hum at best.