Anyone familiar with The League Of Gentlemen will know that it’s nigh on impossible to watch an episode of this astonishingly innovative series without being compelled to reach for the Kleenex. Quite what part of your anatomy you end up wiping, however, depends entirely on whatever floats your psychological boat.

When I ask Reece Shearsmith to reveal how he would describe the show to someone he’d just met and was attempting to seduce, he laughs. Several grimaces of bewilderment later, he laughs again: “I honestly don’t know,” he confesses. “It’s everything and yet… not really anything.”

His colleague Steve Pemberton is equally unwilling to do my job for me.

“I don’t think it’s up to us to describe it,” he muses. “Writing and performing it is difficult enough. You’re the journalist, so you should describe it.”

Bastards. Both men are right, of course. The League Of Gentlemen is indeed “everything and yet… not really anything.” Black, dark, twisted, perverse, politically incorrect, macabre, obscene, profane, depraved, human, disturbing, gothic, big . . . these are just some of the descriptions to have featured in the countless rave reviews garnered by Shearsmith, Pemberton and their two colleagues Mark Gatiss and Jeremy Dyson (who writes but doesn’t perform), since they materialised from the ether and astonished many by making off with the Perrier Award at the 1997 Edinburgh Fringe.

As if to prove it was no fluke, they’ve since recorded a successful BBC radio series, two rapturously received television series and a Christmas special, along the way adding a Bafta, a Sony Silver Award, a Royal Television Society award and The Golden Rose Of Montreux to their haul of gongs for services to comedy. Yes, comedy. Remiss of me not to mention for the benefit of those unfamiliar with their work that The League Of Gentlemen are that rarest of species: a very funny comedy revue.

So funny, in fact, that their live Local Show For Local People has just completed an extended sell-out run in the Theatre Royal, Drury Lane. Despite being the biggest venue of its kind in London, it is dwarfed by Birmingham’s NEC, where a single LoG performance recently attracted an audience of 4,800 people. Not bad for a show which – by its creators’ own admission – is an acquired taste that is unlikely to ever fully capture the public imagination.

Disturbing, funny, perverse and occasionally heartrending, The League Of Gentlemen is set in Royston Vasey, a fictional town in the north of England populated by a bewildering array of grotesques. The kind of place people come from but rarely go to, a stroll through the locale’s blood-drenched streets could result in encounters with any number of sinister inhabitants. There’s Edward and Tubbs, the incestuous shopkeepers who steadfastly refuse to sell anything in their local shop for local people, preferring instead to brutally murder outsiders unfortunate enough to attempt a purchase.

Perhaps you might bump into Pauline Campbell Jones, the pen-obsessed lesbian restart officer who refers to her charges as “dole scum” and gets her kicks by watching telly and flicking herself off to Trisha. One glimpse of creepy German paedophile Herr Lipp’s pallid complexion and squalid lust for young boys in school uniform would send most right-thinking people fleeing back from whence they came, most likely in the taxi of Barbara, the pre-op transsexual with nipples like bullets. There’d be little point in attempting escape. Far better to heed the chilling roadside portent that greets visitors on the way into town: “Welcome To Royston Vasey – You’ll Never Leave.”

Then there’s the more unsavoury locals: Papa Lazarou, the sinister circus ringmaster who “collects” wives; Hillary Briss, the menacing butcher who trades in nose bleed-inducing fatally addictive “special stuff” that may or may not be human flesh, and foul-mouthed Mayor Frank Vaughan, brilliantly portrayed in the television series by comedian Roy ‘Chubby’ Brown (real name: Royston Vasey), one of only a handful of the 40-odd residents not played by Pemberton, Shearsmith or Gatiss. A character and catchphrase-driven series of cleverly intertwined plots, think Evil Dead meets Emmerdale meets The Fast Show and you’ll be some way towards getting a handle on what it is that places these particular gentlemen in a league of their own.

And so to the hard questions: how on earth did the Gentlemen manage to convince their BBC overlords that broadcasting a series in which characters are routinely tortured, mentally and physically abused, maimed and killed in such spectacularly grisly fashion was a good idea?

“I don’t think they ever got to see the show before it went out,” Reece muses, looking to his friend for confirmation. “Well, they knew what we were about because we’d done a radio series and they’d funded that,” explains Steve. “That’s how we got the commission for the television series. When it was on the radio it went out at tea-time, just before The Archers, so some of it was toned down. Obviously at that time there was certain language we couldn’t use but the characters were all there… they just weren’t swearing as much. Then when we got the 9:30pm slot on BBC2 we just ran riot. I think the BBC were shocked, but they never got any complaints when it moved to television. When it was on the radio they got hundreds of complaints, but on television it was restricted to a couple of complaints from dog lovers, because on one occasion we dragged a dog through Royston Vasey by the neck.”

One condition the BBC did insist on was the insertion of a laughter track on the show, a feature that seemed as out of place as a dulcimer solo on a Mariah Carey album in a comedy that was clearly more men behaving badly than Men Behaving Badly. Reece takes up the cudgels: “We didn’t have a row with them over that, as such, more a frank exchange of views. That laughter track’s sort of been our cross to bear. Because the show is often quite grim and dark, they thought that without the laughter track, people who didn’t know what it was might see a couple of minutes and mistake it for some sort of gritty drama.”

At which point, Steve interrupts, laughing: “People who didn’t know what it was could have watched a couple of episodes and mistaken it for some sort of gritty drama! We didn’t have the laughter track in the Christmas special because we felt we’d earned the right not to have one; that people knew what we were about at that stage because we’d done two series. I don’t think they’ll be able to make us use one for the third series now. It’s funny you mention it actually, because out of everything we’ve done - pigs sucking on women’s’ breasts, incest, men sleeping with cows, killing several dogs and burying people alive – the biggest single complaint we’ve got from the public is: ‘Why have you got a laughter track?’. That’s nice in some ways, but certainly not what we were expecting.”

Despite their obvious sense of the macabre, it would be foolish to dismiss these Gentlemen as mere shock-merchants. Their frame of reference includes an astonishing array of well known (and sometimes staggeringly obscure) films, books and plays, and while their monstrous characters may often appal, they are brimming with inhumanity and quite clearly rooted in reality. Royston Vasey may well be a fictional bleak northern backwater, but its creators leave us in no doubt that it could be anywhere. By having all their characters call this one grim place home, bit by bit, Royston Vasey has become a major character in its own right.

“There’s definitely a bit of Royston Vasey in everyone,” muses Steve. “Or should I say, there’s definitely a bit of everyone in Royston Vasey? Most of the ideas and characters we have definitely grew as a result of stuff that happened to us and stuff we’d talked about. It’s just stuff that makes us laugh. It’s weird, actually, because these days different things makes us laugh. We’re in a different world now: we’ve left the world of restart courses, crap theatre companies and charity shops…”

“Yeah,” Reece sneers. “Our next series will probably be based exclusively on characters from The Ivy and The Met Bar. Everyone seems to recognise our characters, so there is obviously a grain of truth in there. We just take aspects of people we’ve encountered, or incidents that have happened to us and take them to the extreme. It’s stuff that makes us laugh and we just happen to be lucky that so many people seem to share our sense of humour.”

Having said that, several women of my acquaintance . . .

“Are frightened by the show,” Steve butts in, finishing my sentence. It’s clearly not the first time he’s heard it said. When he asks me to elaborate, I explain that a few don’t get it and find the content utterly gratuitous , while others are in on the joke but just don’t find it particularly funny.

“It’s a strange one,” muses Reece. “We are aware of that and yet we’ve had five year old children sitting in the front row at some of the shows.”

“We do seem to frighten a lot of women,” continues Steve. “I don’t think it’s a gender thing – you either get it or you don’t. I think you would have to watch The League Of Gentlemen at least twice to get into it. We can’t force people to like what we do because when push comes to shove you’re either local or you’re not.”

What about Roy “Chubby” Brown? Is he local or just in it for the money?

“Oh, he’s local,” announces Steve proudly. “By the time we approached him to appear as the mayor of Royston Vasey he had seen it and was very flattered. He jumped at the chance to do it and we were delighted because having him play the Mayor of himself was just too good a joke not to use. He came down for three days filming and had us in stitches. It was also good in that it legitimised us in the eyes of the people of Hadfield, where the show is filmed. Before he appeared on the scene we were just this weird modern ‘thing’ they weren’t quite sure about. However, once they saw Roy ‘Chubby’ Brown they accepted us.”

It seems a bit ludicrous asking if the Gentlemen have ever found themselves omitting material from their show on the grounds of taste. After all, if the BBC are content to give them yard after yard of free rein, they’re hardly likely to start censoring themselves voluntarily. However, it does seem there was one particular scene which caused them to blanche.

“In the end we decided we just couldn’t show Barbara’s cock being pulled off,” reveals Reece. “We just couldn’t do it.” Not for the first time, Steve tales up the story: “When we did the second series we almost fell into the trap of thinking ‘How can we make it bigger and more shocking and more surprising and more bloody?’. We really went to town on the nose-bleeds, for example. I think now, for the third series, we’ll probably just bring it back down to the more personal stories of the characters. In the last series we went very gothic and very big and could easily have disappeared up our own arses. We didn’t, but we could have. It could have just become vile, and we don’t want to alienate any more people just by making it really unpleasant to watch.”

With the final performance of their London run looming, Shearsmith and Pemberton announce that is time for them to get ready. Along with Mark Gatiss, who has just arrived, they don their tuxedos and take to the stage for an hour of riotous revue, followed by a second-half trip to Royston Vasey which sees the three performing Gentlemen playing a breathtaking number of familiar characters that numbers at least 30. And while anyone previously unfamiliar with The League’s TV excursions may well be mystified by much of what unfolds in the latter half of the show, it is essential viewing for anyone with even a passing interest in things local. Yes, next stop Dublin…

They’ll have no trouble here.