And so it proves week after week in the crude and crudely drawn South Park. Frequently described as "Peanuts on acid", the supremely warped creation of Stone and Trey Parker, his 28-year-old partner in crime, centres on four foul-mouthed nine-year- olds whose misadventures feature (and this is by no means an exhaustive list) UFO sightings, alien kidnappings, genetic engineering, firearms, crack, anal probes, explosive diarrhoea, flaming flatulence, gay pets, mutant turkeys, flesh-eating zombies, a homicidal hand puppet, and, most notoriously, a talking turd.
When it premiered on the US cable network Comedy Central in August 1997, it was clear that South Park's underground days were numbered. Within six months, it was a full-blown, massively hyped, aggressively merchandised pop-cultural phenomenon. Record ratings for a cable programme; covers of Newsweek, Rolling Stone and Spin; $30m in T-shirt sales. Parker and Stone appear together in two feature films scheduled for US release later this year: BASEketball and Orgazmo, a recent Sundance entry about a devout Mormon turned porn star, which they co-wrote and Parker directed. In addition, they're being paid $1.5 million to write a prequel to the hit Jim Carrey no-brainer Dumb and Dumber, and are negotiating a deal for a South Park feature. A South Park soundtrack album is looming, featuring the likes of Beck and Fiona Apple. A possible record deal awaits Parker and Stone's band DVDA (Double Vaginal Double Anal - "a porn term," Stone explains). And the escalating merchandising madness threatens to yield a chocolate bar inspired by Mr Hankey, the all-singing, all-dancing Christmas poo.
How this all started is already the stuff of legend. Two years ago, Parker and Stone acquired a small but loyal following when they made The Spirit of Christmas, a much-bootlegged short film (still widely available on the Internet) that was commissioned by a studio executive as a seasonal video greeting. The five-minute clip established the groundwork for South Park, succinctly introducing its characters - Stan (relatively well-adjusted ringleader), Kyle (Jewish, slightly neurotic), Cartman (fat, easily provoked, shockingly profane), and Kenny (permanently hooded, completely incomprehensible, prone to grisly accidents) - and its chief hallmark: vaguely surrealist iconoclasm (the kids watch in horror as Jesus and Santa Claus come to blows over the meaning of Christmas - at the local mall, no less).
Although The Spirit of Christmas features such decidedly untelevisable lines as "Dude, don't say 'pigfucker' in front of Jesus", Stone claims that it wasn't difficult to housebreak their creation for mass consumption. "Every once in a while, we'd love to be able to say "fuck" or "shit", but other than that, we haven't really had to tone down the show. We tackle the subject matter we want to. Comedy Central wouldn't let us do an episode on the Nation of Islam - I think they were just afraid for our safety - but more often, we're surprised at what they let us get away with."
So far, Stone and Parker have been getting away with scatological humour, celebrity-bashing, and, most impressive of all, thoughtful explorations of awkward themes. The show is irresistible, at once incisive and deranged, when delving into prepubescent confusion - Kyle's bewilderment as a Jewish kid in Colorado at Christmas-time, or Stan's mixed feelings when he finds out that his dog, voiced by George Clooney, is gay (the episode in question has been nominated for an award by the Gay and Lesbian Alliance Against Defamation: it takes 30 minutes to arrive at the same message that took Ellen DeGeneres a season of nervous tics).
South Park's crude, attention-grabbing transgressions make it easy for ome to dismiss it as lowbrow comedy - a notion that Stone doesn't have time for. "I don't see how there can be a class system to comedy," he snaps. "If it makes you laugh, then who cares if it's a fart or a joke about Oscar Wilde? Is it hitting a different part of your brain if it's lowbrow or highbrow?" Just as misguidedly, South Park is often celebrated as an attack on political correctness, when it's more accurate to think of the show as an equal-opportunity offender. Stone says there's no agenda behind the insults. "I don't give a shit about being PC or anti-PC," he says. "We tackle subject matter that we think is funny and unique. We make statements through our humour, but we're not out to make statements. It's never, 'Let's do a show about homosexuality' or whatever. We have our viewpoints, but we don't proselytise, we're just in it to make people laugh."
One favoured device is offhand pop-cultural references: to convey the horrors of ageing, Stan's grandfather forces him to listen to Enya; when his baby brother is abducted by aliens, Kyle urges him to dive off the spaceship by yelling, "Do your impression of David Caruso's career!" (Caruso reportedly found this so amusing that he's asked to do a guest voice); and in South Park's version of Armageddon, evil is represented by Barbra Streisand, good by Robert Smith of The Cure (Smith strolls off into the sunset, while little Kyle shouts after him, "Disintegration is the best album ever!").
Parker and Stone don't necessarily play fair, often randomly resurrecting long-forgotten stars for gratuitous public maulings - in one episode, stocky former sitcom actress and Save the Children spokeswoman Sally Struthers is discovered stuffing her face in Africa, and promptly roasted by villagers ("She's asking for it," Stone remarks drily). The brutally chipper morning talk-show host Kathie Lee Gifford is spared, however, when an assassination attempt by the boys' troubled teacher, Mr Garrison, goes awry. "We would have killed her," says Stone, "but we didn't want Garrison to be a murderer. It would have really changed his character if he'd actually killed another human being, even if it was Kathie Lee."
Perversely, this cheap dig hints at how carefully thought-out the show is. "We feel protective of the kids, but not in some creepy way, and we definitely feel protective of their world," says Stone. "There's a cohesiveness to it that we wouldn't want to break. The world has a logic of its own, which gets more developed every week." Indeed, the fictitious, wintry town of South Park, Colorado - where the main drag boasts a prominent rhinoplasty clinic, and Jesus hosts a call-in TV show titled Jesus and Pals - is the most fascinating slice of small-town America we've encountered since Twin Peaks. Alarmingly, a Colorado resident recently told the Associated Press, "It isn't a comedy. It's a documentary."
On the whole, the show has made surprisingly few enemies. A Connecticut high school tried to ban South Park T-shirts, but otherwise, disapproving voices - mostly concerned with the potential corruption of children - seem largely to have been egged on by journalists in search of a "balanced" story. Stone, for one, thinks that younger viewers - not the target audience, admittedly - are more sophisticated than people think. "This kid that we know came up with a skit for a school report to show how blacks and whites were segregated on the buses, and Cartman was the bus driver. The kid's favourite character is Cartman, but he knows that Cartman's a racist bastard. I thought that was really cool." South Park offers a brutally honest and strangely poignant view of childhood, presenting it as, more than anything else, a continuous erosion of innocence. As Stone puts it, "I think the show's just a little upsetting to people who have an idyllic vision of what kids are like."
Should the shit suddenly hit the fan, Parker and Stone have already prepared their defence, judging by one episode in which the parents of South Park launch a kamikaze protest against Terrence and Philip, a fart- fixated animated-show-within-the-show (the equivalent of Itchy and Scratchie in The Simpsons); an exasperated Stan, in a sudden burst of cogency, notes, "If parents would spend less time worrying about what their kids watch on TV and more time worrying about what's going on in their kids' lives, this world would be a much better place."
'South Park': Sky 1, Sat, 10pm; and on C4 from July.