Hugh Grant leads the way to his offices in Kensington. Simian Films, the production company he runs with Elizabeth Hurley, is spread over the top two floors of a grand white building. On the lower floor, phones buzz and a file overflows with 'invites for Hugh'. He stands in the middle of the room clutching a box of Nurofen Plus. 'I've chipped my tooth and my dentist says there's nothing he can do. I'm on about 30 of these a day. Let's go upstairs.'
He jumps up the stairs and opens the door. He pulls a face, apologises for the stale smell and heaves open a sash window. The room is crammed with magazines and books. A half-empty bottle of whisky sits in a corner. The desk is overflowing and on a lamp hangs a plastic doll of Hurley as Vanessa Kensington-Powers in Austin Powers. Grant sits in an armchair without taking his coat off. He leans back, puts his feet on the edge of a glass coffee table and taps his thighs with his fingers.

Grant drinks a cup of tea awkwardly, trying not to exacerbate the pain in his chipped tooth. 'I shall be slurping, possibly drooling as well.' He holds out the plate of chocolate biscuits: 'You know you want one, bitch.' For a moment, he is Daniel Cleaver when Bridget Jones explains how she used to play naked in his love rival's paddling-pool as a child and he retorts with a sly grin: 'I bet you did, you dirty bitch.'
Hugh Grant has often said that of all the characters he has played - from Clive Durham in 1987's Maurice to Charles in 1994's Four Weddings and a Funeral to William Thacker in 1999's Notting Hill - he is closest to last year's outing as Cleaver. Good looking and well groomed, Daniel is successful and attractive to women but ultimately a sleazy cad who is confused about who or what he wants.

Richard Curtis, who wrote Four Weddings and Notting Hill and co-wrote Bridget Jones's Diary with author Helen Fielding, says that Grant was responsible for the funniest lines in the latter film. 'The scene where he is undressing Bridget and he says, "Silly little boots, silly little dress and these, fuck me, absolutely enormous pants. Don't apologise, I like them. Hello Mummy!" That was all him. I'd have written "What the fuck are those knickers?" or something similar. He fooled around a lot on Bridget because it was in line with his own style of naughtiness.'
The naughtiness is still near the surface but the trademark floppy hair has gone, replaced by a shorter, modern cut that errs on the scruffy side. He looks good, a bit edgier and younger than his 41 years. But the cut wasn't his choice. He had to lose the glossy locks for his new film, the adaptation of Nick Hornby's About a Boy.
'I cut my hair once before to get out of floppy-hair mode and it didn't work. I looked like a lesbian. I really did - I've got that kind of face. I looked like a slightly cross lady golfer. So I grew it out quickly. Then I was prepared to try again for About a Boy.

Hugh John Mungo Grant was born in September 1960 in west London. His mother, who died last year, was a teacher, his father an ex-soldier in the carpet business. He is not sure how to describe his background; he used to say in interviews that he came from a middle-class family but his mother used to berate him: 'No darling, you're a gentleman.' The family didn't have any money - he won a scholarship to Latymer School in London and then to Oxford University - so he supposes that they might be thought of as lapsed gentry.
The young Hugh appeared in school plays without harbouring any desire to take acting seriously. 'I was very moving as the White Rabbit in Alice in Wonderland. We did Dr Faustus, where I was very bitter because I wasn't Faustus, I was just his servant. But I gave quite a good, bitter performance.' He laughs and then frowns.
'What else did we do? Well, I did play a lot of girls.' A big grin. 'The head of drama, now sadly dead, did kind of enjoy young boys dressing up as girls. I was very good as Gretl in The Sound of Music. I wore a white dress with a blue satin sash.' Did he enjoy it? 'Yes, very much.' He slips into the filthy voice. 'I've kept the dress and sometimes I slip it on.'

When he went to Oxford, he continued to act, but always had trouble because of his inability to control himself on stage. 'I'm a laugh queen. I have a very bad giggling problem. I'm so thrilled if anyone laughs at my lines that I roar with laughter myself. I did Hamlet with the Experimental Theatre Company at the Edin burgh Festival, the one where we decided to do it in Star Trek costumes. My thing was basically to play it for laughs. I didn't know that you were supposed to be deep when you acted.'

He made his first film, the 'weird and pretentious' Privileged in 1982, while still at Oxford. The film was screened in London and he was immediately picked up by the William Morris agency. He deferred his place at the Courtauld Institute, where he had planned to do an MPhil in history of art, then realised he wasn't really interested in the subject; it was simply an affectation.

Yet acting was not to feed his soul, either; he just happened to be good at it. Richard Curtis first met Grant at an audition for Four Weddings where he talked seriously about giving up acting. 'He said it was degrading and demeaning and he wasn't any good at it, so it was time he stopped. Then he performed little snippets of sketches, Noël Coward's take on the Nativity or something like that, and I thought it was such a shame he was giving up acting because he was very funny.'

Grant went on to experience international success with Curtis in both Four Weddings and Notting Hill, but Curtis, for whom Grant has become something of a muse, says he still seems confused about acting: 'I think it's not quite his cup of tea, even though he does work very hard at it. He has managed to turn it into a proper job; if you look at his scripts, there are little notes all over his lines. If he had experienced a couple of bad years, he might easily have moved on, though I can't imagine what to.'

It's almost a decade since Hugh Grant decided Four Weddings was worth a risk, and in that time he has become our greatest romantic-comedy export, not only because of his good looks but also because of his perfect comic timing. 'He's handsome and genuine and extremely funny,' says Curtis. 'It's the Cary Grant characteristic.'
When Grant was on holiday in Thailand a few years ago, he was pestered by a Russian healer who told him he had the worst aura she had ever seen. When he finally allowed himself to be examined, she told him he was 'blocked creatively and in most other ways'. She then waved her hands over him to improve his aura. 'Not easy to keep a straight face.'

Now 41 and single, Grant is a little concerned about being so blocked that he will be on his own forever. He admits to being envious of his brother Jamie, an investment banker. 'Jamie has a wife he adores and who adores him, and two fantastic children, and they're just really happy without being smug or anything. It's annoying.'
Is he looking for a wife and children? 'Well, it just gets awkward at certain times of the year. It gets to Christmas and it feels very uncool.' That doesn't answer the question. 'Er, well yes, I think it is what I'm looking for. But then - let's not forget - I'm blocked.'

Ironic then, that Will, his character in About a Boy, is initially similarly blocked, looking for love but scared of responsibility. 'Oh, I'm not as bad as Will. I don't think. You know, I am capable of... I think I've got a sentimental side, which, as one gets older, comes out more and more. All kinds of films make me cry. Almost anything with children in it makes me cry.' He laughs. 'And animals. So I don't think I'm frozen, not in the way Will is at the beginning.' He stands up. 'I'm off for a pee.'

While he is away, I look at the wall of magazines, most of which feature Elizabeth Hurley on the cover. He returns, sits back down in the armchair and looks downcast. 'Those magazines are almost entirely E. Hurley.' I ask about his involvement with Hurley's baby and he shrugs. 'Well, I mean they've already invented a role for me which I wish I could say was true. They say I've been this wonderful rock of support and I'm sorry to say I'm not sure I have been.'
He goes over to his desk and flicks through a diary. 'Is today the first day of Lent? No? Oh well. I was thinking of giving up alcohol for Lent. I once gave it up for January. It was as bad as you imagine it's going to be. I just couldn't go out for 30 days. Or if I did go out for dinner with people, I'd tell them to bring a book because I was so boring.'
He stands up straight. 'Do you want to go to the pub? Well, to the Polish Club up the road? I don't know why but I'm very fond of it. It's a very, very shabby place where lost Poles go to drink vodka.'

We leave Simian Films with Hugh Grant in a baseball cap pulled down over his glasses. He is short-sighted and has been considering corrective laser surgery but isn't quite brave enough. He talks about never going to see his beloved Fulham now that they are in the Premiership, now that they are fashionable, despite the fact that he has been going to Craven Cottage regularly since the age of seven or eight.

He lives in the same street as Fulham manager Jean Tigana, who never recognises him and looks at him as if he were mad each time he bumps into him in the newsagent and congratulates him on the team's performance. 'The PR girl at Fulham says he's so obsessed with football that he hasn't seen a film since 1973.'

He took up golf a few years ago, thinking he wouldn't enjoy it, and is now addicted.
'I take it much too seriously. Yes, I am competitive. I used always to play snooker for money and I do the same with golf; I like a little edge. I'm one of those tragic golfers with lots of money and not much talent.' He laughs. 'I'm loath to say I'm a golfer. It's tantamount to saying I masturbate a lot; it's so uncool and unsexy, but there's no point hiding it.' Masturbation is unsexy? 'Not for girls. It's to be encouraged.'

At the Polish Club, we order beers with Bison Vodka chasers. I ask if he is going to do the sequel to Bridget Jones's Diary, as rumoured. He says only if he would be letting everyone else down by not doing it. 'I certainly don't want to do it, to be absolutely honest; it's like getting back into wet swimming trunks. And I'm not sure Renée is ever going to pile on those pounds again.'

We talk about fame as an aphrodisiac. 'Well, I've found that it has helped. But chatting up is still a misery. I'm bad at it until about three drinks and then I'm very, very good. Fame as an aphrodisiac? Hmmm. Well, I used to fancy famous girls, definitely.'

Does he still fancy them? Does he work with actresses he's had a crush on for ages? There is a long pause. 'Umm... well, I do frequently fancy the girls I'm working with, particularly if I have to snog them. There's something so fabulous about two strangers being made to kiss. I think being on set is a very sexy atmosphere. Extremely sexy. Even if I don't really fancy the actress, I always get a stirring.'

He drains the vodka and shouts something odd, possibly in Polish. 'In the past, I've had to ask the director and the crew to hang on for take three because I have to wait for this stirring to subside. It can be embarrassing. There was one scene, I can't remember when, where I had to walk across a room and I definitely had to wait for everything to settle down.' He lets loose the dirty laugh. 'I'm drunk now. Fancy another Bison?'

Hugh sits back in his seat and talks about playing hide and seek with girls at a Polish disco when he was 15. He didn't find it difficult going to a boys' school because Latymer always arranged extramural activities with Godolphin, the nearby girls' school. 'I remember the unbelievable sexual tension of the film society. I remember seeing Battleship Potemkin, me sitting in the front row next to a Godolphin girl I'd never met before in my life and our knees touching and my hand on her thigh. Fucking great.'

When he stops, he is almost breathless. Is he nostalgic for those days? 'Yes, I am. In fact, I'm currently trying to write a film - it's a comedy that is rooted in a teenage past.'
Writing a script about teenagers has encouraged him to think about the past more than usual. This has occasionally proved frustrating. He realised he has lost the diary he kept more than 20 years ago when he travelled round Italy on his own, studying paintings in his 'pretentious art phase'. And there's a record he made with his mother for his father back in the mid-Sixties, when he was five or six.

'We went to this booth in Selfridges and my mother said in her incredibly Fifties voice, "What is Hughie going to say for Daddy?" There was a silence while I froze. Then I sang "Away in a Manger" before telling Daddy how much I loved him. We used to torment my mother with this record and I must have taken it to Oxford to play to my friends. Anyway, I realise that I've lost it forever and I can't bear it.' He sounds tortured and it's hard to tell if the capricious Hughie is being serious or not.

Without warning, he smiles. 'There was also a very good record of me and Elizabeth singing - what's the song Nicole Kidman and Robbie Williams did? Oh yes - "Something Stupid". Well, we did that in this recording booth at Venice Beach. They didn't tell us that, while it's being recorded, the song is also being broadcast to the beach. So we came out and everyone applauded. Not sure where that record is, either.'
He stands up and puts his coat on; he has a meeting with the international distributors of About a Boy and is already running late. He puts his hands in his pockets and finds some crumpled notes, but not enough to pay for the drinks. He pulls the baseball cap over his eyes. He winces. 'Sorry, I would love to be the consummate gentlemen but it seems I can't quite afford it.'