Imagine a remake of “Meatballs” or “The Bad News Bears” with the raunch quotient dialed up a few spins and you’re ready for “Nature Calls,” a brazenly foul-mouthed but ultimately soft-hearted comedy of bad manners that could forage for respectable theatrical biz before enjoying heavy rotation as VOD, vid-rental and pay-cable staple. Some may complain about the pic’s frequent tactic of trolling for laughs by unleashing F-bombs and similar vulgarity around young children. But then, it’s doubtful that too many of the easily offended will wander unawares into this untamed territory in the first place.

Patton Oswalt amusingly conveys both cheery optimism and anxious obsessiveness as Randy, an assistant scoutmaster determined to maintain the troop once run by his ailing dad (John Tobias). Trouble is, the few boys in his group are tired of boring campouts in parking lots and opt to ditch the latest weekend outing in favor of a sleepover that Randy’s estranged brother, Kirk (Johnny Knoxville), is hosting for his newly adopted African-born son, Dwande (Thiecoura Cissoko).

Kirk, who strayed from scouting years ago, made his fortune selling ATM machines, and now lives with his astonishingly patient wife (Maura Tierney) and Dwande in a spacious McMansion stocked with multiple bigscreen TVs and other playthings irresistible to adolescent males of all ages.

But Randy improbably manages to lure Dwande and his sleepover guests out of the funhouse for an unauthorized camping trip deep in the woods. Kirk follows in hot pursuit, accompanied by Gentry (Rob Riggle), his gung-ho security chief, and Caldwell (Patrice O’Neal), a scout’s dad with his own reasons to be angry with Randy.

Oswalt’s relative restraint (emphasis on “relative”) allows him to serve more or less as the anchoring straight man among the grown-up guys in the cast. His adult male co-stars — including Knoxville, Riggle, Darrell Hammond as an officious park ranger, and Eddie Rouse and Ivan Dimitrov as Randy’s none-too-bright assistants — come off as cartoonish caricatures, often to hilarious effect.

O’Neal, who died shortly after completing “Nature Calls,” and to whom the pic is dedicated, here gives a performance suffused with profanely funny bluster. Tierney makes the most of an underwritten role, especially when her character deals with the amorous overtures of an underage house guest.

The boys, of course, benefit greatly from their weekend adventures, even though their experiences include witnessing at least one potentially traumatic incident and having a close encounter with a nude female motorcyclist who apparently vroomed in from 1971’s “Vanishing Point.” Things turn out pretty well for the grownups, too, although it’s clear from the multiple happy endings that writer-director Todd Rohal (“The Catechism Cataclysm”) doesn’t have his tongue very far from his cheek.

Some abrupt transitions and a couple of barely developed subplots indicate last-minute editing-room surgery. Overall, though, tech credits are solid.

Nature Calls

  • Production: A Troop 21 production in association with Muskat Filmed Properties. Produced by Lisa Muskat. Executive producers, David Gordon Green, Michael B. Clark, John Hodges, David Bausch. Directed, written by Todd Rohal.
  • Crew: Camera (Deluxe color) Steve Gainer; editors, Alan Canant, Nat Sanders; music, Joseph Stephens; production designer, Matthew Munn; set decorator, Theo Sena; costume designer, Jacki Roach; sound, Richard W. Murphy; supervising sound editor, Ron Bochar; assistant director, Scott Lazar; casting, Avy Kaufman. Reviewed at SXSW Film Festival (Narrative Spotlight), March 10, 2012. Running time: 80 MIN.
  • With: Randy - Patton Oswalt<br> Kirk - Johnny Knoxville<br> Gentry - Rob Riggle<br> Janine - Maura Tierney<br> Mr. Caldwell - Patrice O'Neal<br> Dwande - Thiecoura Cissoko<br> Ranger Deakins - Darrell Hammond<br> Little Eddie - Eddie Rouse<br> Ivan - Ivan Dimitrov<br> Stuart - John Tobias