The latest foul-mouthed comedy cast in the Judd Apatow mould is a genuinely funny escapade that milks every guffaw from its predictable fish-out-of-water scenario.

Role Models doesn’t deviate once from a well-trodden path of breast gags, wanton stupidity and hard fought redemption but David Wain’s film has an undeniable charm and some terrific one-liners as it extols the virtues of fraternal love.

The lively patter between lead stars Paul Rudd, who co-wrote the script, and Seann William Scott, as a pair of puerile 30-something degenerates forced to think like adults for once, wins us over.

Inevitably, by becoming mentors to two troubled youths, these men behaving badly grow up and finally lead by example, proving that responsible adults aren’t afraid to don copious face make-up and tights in public.

Danny Donahue (Rudd) and his best buddy Wheeler (Scott) work for the same energy drink company, touting a noxious, fizzy brew called Minotaur to bored children.

After an altercation at one school, they are sentenced to 150 hours community service and reluctantly head for the Sturdy Wings mentoring programme run by reformed addict, Gayle Sweeny (Jane Lynch).

She assigns Danny and Wheeler a troubled kid apiece, fantasy role-playing game obsessive Augie (Christopher Mintz-Plasse) and foul-mouthed 10-year-old Ronnie (Bobb’e J Thompson), and instructs the men to use their allotted time to get to know the boys and bring them out of their shells.

At first, Danny and Wheeler fail to connect with their charges, content to sign off the 150 hours and return to their unfulfilled lives.

Very gradually, the best friends realise that Augie and Ronnie need their help to cope with estrangement from selfish parents and feelings of abandonment, and they just might be the no-hopers to give these kids a second chance at happiness.

Role Models isn’t big, it certainly isn’t clever but Wain’s comedy is a guilty pleasure with plenty to snigger at.

Quirky supporting performances snaffle the belly laughs.

Lynch is hysterical as a one-time druggie turned gung-ho youth counsellor, whose unconventional pep talks combine toe-curling confessions with tough love.

Mintz-Plasse plays a geekified version of his signature role as McLovin’ in Superbad while Thompson is like a pint-sized Chris Rock, unleashing more swear words and filth than the rest of the cast combined.