"JUST BECAUSE WE HAVE a house and a baby doesn't mean we're old people," Seth Rogen muses at the beginning of Neighbors. He's delusional, of course—it totally does—and the gods aren't about to let hubris of that magnitude slide. Zeus snaps his fingers and a frat house appears next door to Rogen's adorable new home. ACCEPT IT. NO ONE STAYS COOL FOREVER, Zeus thunders. Zac Efron emerges from the fraternity and takes his shirt off. Old age trembles and is vanquished. Youth prevails forever.

Or something, anyway. Neighbors pits cranky-old-man Mac (Rogen), his wife Kelly (Rose Byrne), and their shockingly adorable baby Stella (some baby) against the shenanigantastic fraternity next door. When the frat moves in, Mac and Kelly can't decide if they want to hang with the fraternity brothers and prove they're still fun, or call the cops and shut that shit down. When they ultimately opt for the latter, it's tantamount to a declaration of war. There will be pranking!

The surprising thing about Neighbors is that it's actually a buddy comedy, and the buddies are the married couple. Rose Byrne is great as a stay-at-home mom who both loves her kid and is super, super bored with being stuck on baby duty. She's in on every joke, even the one that has Rogen milking her lactating breasts when the breast pump breaks after a night of heavy drinking. In a worse movie (Grown Ups), a breast-milking scene would be played purely for gross-out laughs (seriously, that happened in Grown Ups). Here, it's actually kinda sweet. She and Rogen are a team in a way that onscreen couples rarely are.

The frat house, meanwhile, is full of charismatic youngsters led by president Zac Efron. James Franco's little brother Dave plays the house veep, a role he surely earned on his merit as an actor alone. The frat seems very authentic and true-to-life. (Note: I fact-checked frat life against ABC Family's Greek, a 100% accurate representation of life within the fraternity system.)

Neighbors is a decent comedy. Clearly, the actors were encouraged to "riff"—the result is a ton of sloppy improv anchored by likeable characters and a few really solid jokes. In the hours of outtakes cluttering up a hard drive somewhere, there are no doubt alternate storylines that go more in depth with secondary characters like Mac's boss; Lisa Kudrow doing her best Allison Janney impression as the dean of the college; Hannibal Buress riffing as a diffident neighborhood cop. (Comedy fans, keep your eyes peeled for Natasha Leggero working a street corner.)

The best gags are physical: A drunken kitchen-floor sex scene, an extended fight scene involving lots of ball-cupping. Neighbors also features not one, but several torso-by-torso comparisons of Efron and Rogen; Efron's abs make Seth Rogen look like a factory reject, a cookie you eat right away because it's too misshapen to put on a fancy plate.

It's sort of annoying that Neighbors thinks it has to have any sort of moral, but there's some Serious Business about growing up crammed into the end. Spoiler: It's not the worst thing in the world! Babies are cute! If you need someone to explain those facts to you while you laugh at some dick jokes, then Neighbors is the middle-of-the-road comedy for you.