It’s easy to accuse Paul Rudd, who makes his big-screen writing debut and stars in Role Models, of borrowing a page from his pal Judd Apatow’s crass but disarmingly soft-hearted playbook for this comedy about a criminally irresponsible pair of adult mentors. But what exactly does that mean? That it’s funny?

Yes, Role Models is just what you might expect, a juvenile farce that verges on the subversively obscene without ever fully committing, that celebrates a sort of nihilistic, anything-goes raunchiness before revealing its heart of gold. There’s nothing wrong with a formula like this when it works. Here it does.

Sure, it might make for a nice change of pace if Apatow and his de facto comedy troupe could rein in their tendency to romanticize male bonding with sentimental about-faces, effectively calling off the dogs after a spirited exchange of barbs. Then again, it might not. The world doesn’t need another Step Brothers.

Rudd and co-star Seann William Scott’s styles complement each other comfortably. Rudd’s deadpan often leaves him a bemused witness to the madness around him, while Scott, in movies like The Dukes of Hazzard and American Pie, hurls himself headlong into the absurdity. They share a goofy, engaging chemistry as Danny and Wheeler, Peter Pan-in-midlife-crisis types who find themselves required by the courts to spend time with two troubled kids after Danny, in a fit of energy drink-fueled rage, crashes their monster truck into a schoolyard.

There’s nothing surprising about the rocky road to friendship that awaits Danny, Wheeler and their young charges. Augie (Christopher Mintz-Plasse, of Superbad) is obsessed with medieval fantasy, and if his parents think it odd that he’s partial to wearing capes and loose-fitting tunics, he and his fellow swashbucklers do not. Ronny (Bobb’e J. Thompson) is short, fatherless and friendless, dropping F-bombs with the uncensored zeal of a young Eddie Murphy. Neither is an obvious match for his big brother, and it is to director David Wain’s credit that he treats the awkward attempts at cross-generational camaraderie as something more than a premise for crude punch lines.

Of those, there are many, and a lot of them are actually funny. (Even most of the zingers that miss their mark are enough to elicit a smile.) And that pretty much sums up Role Models. It's not about to redefine the comedy universe, but it's competently made with a cast that knows how to bring out the humor in material that's sharper than you might expect. That should be enough.