It's not a joke. Chubby Oates, current holder of the world "not-smiling" record, is planning a fresh attempt.

The comedian who has devoted his life to making other people laugh, will try to keep a straight face for more than two hours and 23 minutes - his current world record.

It sounds easy. But Chubby is up against the general public, who will be invited to crack him up in almost any way they like. Tickling is out since there is a strict rule of no physical contact.

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Chubby set the first record 12 years ago - notching up two hours 14 minutes without a smile. Five years ago he struggled to add just nine more minutes when he faced the public in a shop window in London's Oxford Street.

But it was no walk over and he admits it's the most bizarre things that can induce a fit of giggles. Last time round he just managed to stifle a chuckle at the surreal sight of a fat baby sucking on what looked like a banana.

It took an even more unusual rib-tickling experience to finish him off.

"I broke down when an old lady quite suddenly produced a black pudding from her shopping bag, without even raising her eyes to me. But she knew just what she was doing," says Chubby.

His new attempt will be made in a shopping centre in Surrey and Chubby will face further pressure in the form of fellow comedian Kevin McCarthy, who plans to wrestle the record from him.

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Kevin is a self-confessed misery guts who has been practising by scowling at his wife.

"As a comedian I find I don't laugh at other people's jokes because I've either heard them before or I immediately start thinking how they could have been told better," says stand-up Kevin, who has appeared on TV shows including Chris Tarrant's Prove It and Jo Brand's Through the Cakehole.

He will even bring along a few "sobering mementoes" such as his tax returns, which are almost guaranteed to suppress a bout of hysteria.

It could be days

"I think it will go one of two ways. I'll either last five minutes or five days. I'm definitely going to give it my best shot," says Kevin

Tony Edwards, who is organising the event, expects a long queue of wannabe comedians keen to make the lads laugh.

If the event is a success he even plans to list the achievement with the Guinness Book of Records, making for a really serious contest.

Do you have joke to make Chubby and Kevin crack?

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