RICHARD WILSON said we could meet either at Le Caprice or The Ivy, ignoring the possibility of other, perhaps humbler, restaurants. When he turned up at The Ivy and I broke it to him that we couldn't take photographs inside, he said 'Quite right, too]', and meekly submitted to being dragged out into the street for 20 minutes.

Not behaviour one could expect of Victor Meldrew, the hero of BBC1's hugely popular Sunday night sitcom, One Foot in the Grave. He would have demanded why the hell I hadn't checked; he loathes being mucked around, and would tell you so in no uncertain terms. As Victor, Wilson voices the exasperation and rage of all right-thinking people at everything inconsiderate, careless, slipshod and just plain wrong with modern life. From neighbours who throw their rubbish in your skip to the abuse of old people in residential care, Meldrew is there, spluttering and fuming, wondering what has gone wrong and why people don't have decent manners any more.

'He is a victim: if society were different, Victor would be happy,' thinks Susan Belbin, the producer and director of One Foot in the Grave. 'He takes time to complain about things that irritate us all. He has become, for the moment, the voice of the people.'

A couple of weeks ago the sitcom turned on the abduction of a baby; last week Victor lost his temper with a couple of 10-year-olds who had, he assumed, painted stumps on the front of his house and lobbed their ball through his window. His fury - initially shocking because he had no proof - was vindicated when the children screamed that he was a miserable old git. One Foot in the Grave teeters on the edge of tragedy, and it takes impressive acting to make it funny.

The part was written with Richard Wilson in mind (although at first, he turned it down): his distinctive voice and lugubrious manner are crucial to its success. The first series started modestly enough, with 8.9 million viewers, and the second did OK; but the current series has outstripped all previous sitcom records. Recent episodes have attracted 17.5 million viewers - a million more than Del Boy pulled in for Only Fools and Horses at its peak. The Sun is running a competition to 'paint Victor Meldrew', while in the heavier papers professors of sociology and deconstructionalists weigh in with their views on the Meaning of Meldrew.

The scripts have undoubtedly improved: 'Over time,' says the writer, David Renwick, 'the writing has been cross-fertilised by Richard's performance.' Tonight Wilson is required to carry off the whole episode by himself (a demand made before in sitcom only of Tony Hancock). Waiting at home to be called for jury service, Victor muses on anything from switchboard operators who leave you hanging to the right to life of woodlice. As always, there is a hint of something awful about to happen. 'The show has an attitude,' says Renwick. 'Cynical, resigned, aware of the soddishness of circumstance and hostility of the world around us.'

Richard Wilson is a quieter, politer, more easy-going man than the character who has, at the age of 56 and after a long, solid career, suddenly made him famous. It is odd, he thinks, that Renwick saw Victor in him: 'I hardly lose my temper at all. It's too much of an easy way out to frighten people.'

He grew up in Greenock, near Glasgow, the son of a shipyard timekeeper. 'I've always said that I was working class, but I might have been upper working class. All the shipyard foremen wore bowler hats: my father wore a bowler hat. He worked overtime without pay, used to bring work home every night, worked his socks off. I don't think I consciously thought he was silly at the time - although looking back on it, I realise he probably was.

'That, I suppose, is part of the reason I am a socialist - although some would say a champagne socialist. I feel the gap between the rich and poor is too great. The west of Greenock was full of the most gorgeous, beautiful houses, the east was full of the docks.'

Wilson thought vaguely of becoming a vet or going to sea, and once suggested to a teacher that he might like to act. 'She said, 'Don't be silly, boy: you can't speak.' I met her recently and she said, 'I never said you couldn't speak, I said you spoke into your beard; and if you don't mind me saying so, you still do.' '

He has always been self-conscious about his voice. 'I never thought of it as distinctive; I just thought it was nasal. I had a terrible time at Rada - I loved the place, but I had a terrible time voice-wise. I had to have private lessons. It made me quite ill with nerves the first year. Only recently have I started to have any pride in my voice.' He still takes fortnightly lessons with Patsy Rodenburg, the voice coach at the National Theatre.

But the voice is vital to the characterisation of Meldrew - taut and tetchy (although it is a major reason why he originally turned down the part, thinking that he sounded too Scottish). Any limpness of delivery would ruin Victor's invective against loutish drivers or waste disposal units that don't work. 'His enunciation is wonderful,' says Susan Belbin, 'he bites off the words and munches them.'

Wilson left school at 17 and worked for 10 years - mostly at Paddington General Hospital as a lab technician - before applying to Rada; he has hardly been out of work, acting or directing, since. The directing developed out of an interest in improvisation that he maintains to this day: he is teaching an improvisation class next month at The Actors' Centre. 'The class is called 'Improvisation, a guide to the actor's thinking' which sounds a bit pompous, but it's what I think: most actors worry about the words, but the words are only a guide to a greater subtext. You've got to work out from the text, from the clues in the text, who you are, what the background is. It's what comes between the lines that interests me.'

Almost invariably, he has directed new writing: his next production is an award-winning new play at the Manchester Royal Exchange. 'The exciting thing about theatre and television is reflecting the society we're living in now. Besides, I don't think I'm intellectually equipped to direct old plays.'

Sheila Hancock (whom he directed in Prin, among other things) describes a rather luvvy directorial method: 'He starts with daft games: you have to throw bean bags around. And he once made me do an improvisation down a nuclear shelter - hours sealed in this tomb, with only tinned beef to eat. But I don't know a single actor who doesn't worship the ground he walks on. I have worked with more than 500 directors, and he's very near the top, if not the top. He hates tricksiness, affectation and easy laughs.'

Wilson is famed for his parties, which he organises with meticulous attention to detail. He lives in Hampstead, and most of his close friends are actors (Anthony Sher is one), but he makes a rule of not talking about his private life, on the grounds that 'actors should be metamorphic: I feel the more people know about me, the more difficult it is to act'.

He favours flamboyant clothes, yellows and pinks; he was wearing a dashing, and very posh, maroon shirt for lunch. 'A present from an actress friend,' he explained. 'I spend a lot of money on clothes. I suppose part of that is about hating ageist categories - I hate the idea that when you get to a certain age, you should stop doing anything . . . it's rubbish. I do a bit of work for Age Concern, opening offices and so on, and I support them from that point of view, and in their campaign against ageist words - I dislike all that.'

Anthony Holden, the royal biographer, wandered over during lunch and asked Wilson for his autograph. He is having to get used to public adulation; and for a rather reserved, quite taciturn man, 'a lot of the time it's confusing: if someone meeting you starts to blush, for example, as though you're someone who should mean something to them. You're just an ordinary person, very dull, and yet these people are saying you're not. I want to say to them 'Don't be silly'. Oh, perhaps you'd better not write that; I don't want to insult them. I'm very touched as well sometimes, absolutely humbled.

'But I have started avoiding the tube. For a long time I couldn't afford a car, and then I resisted buying one because I thought I was going to cut myself off. Travelling on public transport is quite important for an actor.'

The title One Foot in the Grave is meant, he says 'to be ironic'. 'Victor hasn't got one foot in the grave - or if he has, the other foot's definitely well out. I don't think the show's really about old people at all: I get letters saying 'My fiance is just like you, and he's only 22', and a huge number saying 'You're just like my husband'.' Wilson devotes quite a lot of time to keeping his own feet out of the grave: playing squash and swimming twice a week, and 'stretching, push-ups, press-ups, and vocal exercises' every morning.

Renwick is angered by the usual summing up of Victor as 'grumpy', and of his wife Margaret, (played by Annette Crosbie,) as 'long-suffering'. 'If anyone's long-suffering, it's him. There was a line last week about him being sensitive, and that's what he is: over-sensitive to life. He's on a very short fuse. I'm funnelling the whole of life's miseries through him. He's a Christ-like figure.'

Victor is grumpy: that's what is funny, that he minds so much about the teaspoon that always stays in the washing-up bowl. But he is also incredibly nice - protecting his childless wife from the knowledge that the little girl she loved has turned into a delinquent; avenging the old man beaten up in residential care. Richard Wilson has struck a chord with all those who feel that they would be more thoughtful, more socially concerned, nicer - if only life wasn't so damn harassing.

(Photograph omitted)