Michael Palin is the sort of character who might well star in a Roger Hargreaves children's book called Mr Nice. Like David Attenborough, his fate is always to be known as a good bloke. And he's a bit fed up with it. "The use of the word nice has become a millstone," he sighs. "People think I go around saying `Hello trees, hello sky'. The word nice is pretty close to meaning someone ineffectual who has no opinions of any sort. "Although I wouldn't force my opinions on anyone, I do it more out of a canny estimation of how to get by. I'm ruthlessly nice, and it's bloody hard work. I'm not saying I go around strangling kittens; it's just the vapidity that niceness suggests. I don't know many complete bastards. It seems onerous that I should be the one branded Mr Nice."

Unfortunately for Palin, he seems unlikely to shake off that tag with his latest venture, Full Circle, a major 10-part BBC1 documentary about circumnavigating the Pacific Ocean, with the inevitable tie-in book, audio tape and video.

For all his protestations, it is this very niceness which attracts people in their millions to Palin's work. He involves viewers, draws them in and makes them feel like his friends. He is the kind of person people would love to have dinner with. Who else could have netted pounds 10m for a programme about the Sudanese Desert? With typical hyperbole, people inside Television Centre talk in hushed tones of Palin as "the man who saved the BBC".

In explaining the appeal of his travel shows - he has enjoyed hits with Around the World in 80 Days and Pole to Pole - Palin talks about the empathy between the viewer and himself. "You're not travelling with an expert," he muses. "You're undergoing experiences with a person who is responding like you would. We don't pretend we know everything and you know nothing. It's a voyage of discovery for everyone."

He is also wary about bringing along too much hi-tech baggage. "I take a map, but that's it. I don't speak any languages except French and that's not much use in Japan. I don't have the practical skill to survive in, say, the Amazonian jungle. I have an average person's abilities. What I add is that I look for the comedic angle. Humour is very important as a way of surviving."

But Palin never likes to tack the humour onto situations. "I don't want to be poking my head into every frame saying, `Here's a wacky thing'. I want to let the pictures speak for themselves. Things do happen which are naturally funny - usually to do with lack of communication. But as soon as you force the humour, it becomes a personality show."

Journeying into so many uncharted quarters of the globe, it would be easy for Palin to slip into "Let's have a cheap laugh at the expense of these crazy foreigners" mode. "The danger is that you say, `This is a funny country'," Palin admits. "You should celebrate difference. You learn more about yourself that way than you do with amusing observations of other people's funny customs. That can easily be patronising. In fact, Janet Street-Porter said I was patronising in Around the World in 80 Days."

Perhaps surprisingly for one so universally popular, that is not Palin's only brush with criticism. He fell victim to the "tall poppy" syndrome when his play, The Weekend, opened in the West End. "I was comprehensively combine harvested," he gulps at the memory. "Richard Wilson took the lead. He was known for One Foot in the Grave, and I was known for television travel. It was as if the critics felt we had cobbled the play together in order to hijack their patch. They're very protective about the West End. I'd say the play was better than the damning it got."

He is similarly prepared for a backlash against Full Circle. "I regard every programme as a minefield," he worries. "You just don't know how people will react. If they say `we're bored with him now', I'll have to find another way of doing things. For every article that says `Michael Palin is the nicest man in Britain, he's never done anything wrong', someone else will say `Right, let's get him'. A lot of criticism is criticism of other criticism."

Palin will manage to dodge further attacks, however, as long as his work continues to exude warmth. All his roles - from Ripping Yarns and The Missionary through A Private Function and A Fish Called Wanda to the travel presenting - have a recognisably humane streak to them. Even in the more grotesque Monty Python sketches, he always communicated a sense of pathos. Just look at his achingly believable portrayal of the put-apon teacher in GBH. It may pain him to hear this, but I can't ever see him being cast as a Bond villain.

In the first episode of Full Circle, Palin has a chance to demonstrate his sensitivity when he escorts a former inmate around a remote Russian gulag. In a deeply touching scene, they find human bones in the location where the ex-prisoner was held more than 50 years ago.

Later on in the series, Palin travels through "The most dangerous street in Bogota, where all the druggies hang about. We met a male prostitute who was HIV-positive and had been knifed. He was somebody whose life was the hardest you can imagine, and he gave us a smile. It's all about communication.

"That's the way life is," Palin reflects. "You see things which are unpleasant or moving. You don't want to be sentimental or sanctimonious or the man from the Serious Documentaries Squad, but to be a jolly comedian all the time is not natural."

`Full Circle' starts tomorrow at 8pm on BBC1. The book is published on Monday


1943: Born in Sheffield, son of an engineer.

1962: After Shrewsbury School, he went to Brasenose where he performed his first comedy material at the Oxford University Psychology Society Christmas party

1964: Appeared with Terry Jones in the Oxford Revue at the Edinburgh Festival

1966: Wrote with Jones for various TV shows including The Frost Report and The Late Show

1968: Wrote for Marty Feldman and performed Do Not Adjust Your Set

1969: Joined Graham Chapman, John Cleese, Terry Gilliam, Eric Idle and Jones for Monty Python's Flying Circus

1974: Monty Python and the Holy Grail

1977-79: Ripping Yarns

1980: Time Bandits

1981: The Meaning of Life & The Missionary

1984: A Private Function & Brazil

1988: A Fish Called Wanda

1989: Around the World in 80 Days

1991: American Friends & GBH

1992: Pole to Pole

1994: The Weekend

1995: First novel, Hemingway's Chair

1997: Fierce Creatures & Full Circle