Better known as hapless flatmates Mark and Jeremy in Channel Four's Peep Show, David Mitchell and Robert Webb have since spun more television gold with their sketch show That Mitchell And Webb Look - not to mention the Radio 4 version which preceded it, That Mitchell And Webb Sound.

The Radio Times is already bigging them up as "the new kings of comedy". This year, Peep Show won Best TV Comedy at the South Bank Show Awards and has been snapped up by Fox for redevelopment as a US comedy.

The mighty Ricky Gervais recently said: "The last thing I got genuinely excited about on British TV was Peep Show, which I thought was the best sitcom since Father Ted."

Now on tour for the first time - rising to the challenge of 44 dates with live audiences across the country - Mitchell and Webb are transposing their sketch show to the stage, armed with an array of ridiculous costumes, dreadful toupees and bargain basement props.

The duo's cerebral sense of humour is at its funniest when they take the mundane out of context and twist it into something far more seedy and joyously strange: think alcoholic snooker commentators dribbling beer behind the scenes, or obnoxious flatmates bitching about an unwanted dinner guest and his four legged friend. (It only dawns on you half-way through their conversation about this skinny, sandwich-guzzling, dog-loving freak they are actually talking about are cartoon creations Shaggy and Scooby Doo. By then, you are hooked.) As The Telegraph's Gillian Reynolds put it: "The writers do that magical thing of shifting the accepted perspective on ordinary things so that you suddenly see the ridiculous side.

Reality becomes unreal. It is intoxicating."

Mitchell, the posh, butler-like, square one says: "I think basically we like quite wordy, quite cerebral ideas but with some stupid falling about involved in their exposition. I think we're definitely not very wacky, and I think we're definitely not not-at-all-wacky."

"We are by no means afraid of the wack,"

agrees Webb, the more robust and outwardly enthusaistic of the two.

Raised respectively in Oxford and Lincolnshire, Mitchell and Webb, both in their early 30s, met at Cambridge University.

It was here that they were drawn to the legendary Footlights student theatre club whose glittering alumni include the likes of Peter Cook, John Cleese, Eric Idle, The Goodies, Douglas Adams, Stephen Fry, Hugh Laurie and Sacha Baron Cohen to name but a few.

After appearing at the Edinburgh Fringe, and writing for other performers, they formed a double act.

Since graduating they have done everything from writing scripts to performing in sketches and sitcoms on radio, stage, television and, in the pipeline, film - Mitchell is set to star opposite Michelle Pfeiffer in rom-com I Could Never Be Your Woman. They have also appeared in adverts, panel shows and list shows.

"Any double act have to be really good friends," says Webb, who recently asked Mitchell to be best man at his wedding in December. "You need a strong connection.

You can't write with someone when you hate their guts. We never fall out.

"We've always found the same things funny and feel that as a double act we're greater than the sum of our parts."

Mitchell and Webb find plenty to amuse in the most unlikely places. "Other people's pain is always funny," says Mitchell, "whether it's someone slipping on a banana skin or Ralph's agonising, unrequited love for Ted in The Fast Show. They're just different sorts of pratfalls. And anything when you know you're not supposed to laugh suddenly becomes funny."

Apart from the comedy of pain, is there a theme which links one sketch to another?

Mitchell thinks not. "In the past, we've never had the nerve to say, We're funny - please give us a sketch show.' But that is really the only premise of the programme.

"You can make a rod for your own back if you say something like, All the sketches are about people who are frightened of change', or, We follow a bar of soap as it's handled by loads of different characters.' "I come out in favour of a joke every time, rather than being straitjacketed by an overarching theme.

"All you can say is that a lot of the sketches have a go at certain attitudes - that's a very good way of coming across jokes. When you're staring at a blank sheet of paper, a great starting point is, What's annoyed me recently?'"

So what of the future? "Sketch-writing is a youngish man's game," says Webb. "The fecundity dries up after a while - you don't see many sketch-shows starring 50- somethings.

"My prediction is that, by our late 40s, I'll be writing bad novels and David will be in Los Angeles taking cameos as English butlers and playing for the Hollywood Cricket Club."

  • Dome Concert Hall, Church Street, Brighton, Thursday