During a divorce, you have to be like the man in the toll booth you must accept change."

Delivered completely straight, such wince-inducing jokes would get most comedians booed off the stage.

Yet coming from Rob Brydon - in character as cuckolded cabbie Keith Barret - such knowingly awful gags have seen him dubbed "the funniest man on TV", so popular that he's currently in the middle of a 51-date UK tour.

Those unfamiliar with Rob Brydon might recognise him as the unlucky traffic warden from Lock, Stock And Two Smoking Barrels, or his roles in 24-Hour Party People and BBC's Kenneth Tynan: In Praise Of Hardcore.

His most famous creation, however, is Welsh divorcee and minicab driver Keith Barret, who first appeared on our screens in 2001 in a series of 10-minute monologues filmed from a single camera fixed to the car dashboard.

The show was entitled Marion And Geoff, referring to Barret's wife and the man with whom she was having an affair. Despite the simple formula, the bittersweet vignettes fast developed a cult following for their combination of the highly comical and deeply poignant, leaving the audience forever unsure whether to laugh or cry.

The element of pathos was increased by Barret's insistence on looking on the bright side of every problem, exemplified by the comment: "The way I see it, I haven't lost a wife, I've gained a friend. I never would have met Geoff if Marion hadn't left me."

The show, which was backed by Steve Coogan's Brighton-based production company Baby Cow, quickly grew from cult status to runaway success, with Keith Barret becoming an unlikely hero in the process, even moving into TV with the Keith Barret Show.

"Keith is a very likeable character," says Brydon of the popularity of his alter ego. "I get a lot of warmth and sympathy from people I bump into on the street. It's also very accessible. I wanted to do something you could get into really easily - you don't need a PhD to enjoy the Keith Barret Show."

Having said that, he agrees that Barret is more complex than he may initially appear: "He seems to be a nice easy-going character but at the same time I hope there's a sharpness there.

"I see Keith as a wolf in sheep's clothing. There's a vein of sadness which makes him a more effective comic creation."

"From Woody Allen to Larry Sanders to The Office, what I have always loved in comedy is the idea of self-delusion. I adore characters who, because of their own flaws, are unable to see the full picture. There's an awful lot of humour in that."

It's this entirely self-deluded character which Brydon has now decided to take on the road. As with the series, he'll be addressing the subject of what makes for a successful relationship or, as he puts it, Making Divorce Work. The joke, of course, is that his character's relationship had been such a fiasco, although again, he is determinedly optimistic: "Before doing the series I found love bewildering. Now I'm merely confused - and that's progress."

Whereas on TV he quizzed celebrities, the live show will see him talking to members of the audience, giving people a rare opportunity to interact live with a TV star. As he says, "I pick a random couple from the audience, get them on stage and ask them about their marriage and their sex lives."

So, finally, any special guests lined up for the live shows? "I shall be talking to a couple from the audience," he replies.

"I don't know who they are but if they're from Brighton, they'll be very special indeed. I'll also answer any question you care to ask - within reason."

Starts 7.30pm, tickets cost £16. Call 01273 709709.