The middle-aged man who answers the glass door could be anyone, though the fact that Boy George has owned this house on a hill in Hampstead for the past 16 years does narrow the possibilities. And it definitely is his house because on the gate posts, as you wait to be buzzed in, you see fans have scrawled messages to him in felt-tip – some are fresh, some faded.

Japanese tourists especially used to track him down here. He thinks they bribed taxi drivers to show them where he lived, then they would wait with their cameras. ‘I’m thinking of putting up a plaque,’ he says. ‘Boy George lives here. Go away.’

He also has a house in Ibiza, and had an apartment in New York, until his unpleasant experience there a couple of years ago, which we shall come to. He moved back to London after that, but not before he had this house ‘exorcised and blessed’. The place has gothic turrets, around which you half expect bats to be circling. Come to think of it, what with his shaved head, there is something of the Uncle Fester about the man himself. There is a blue Star of David tattooed on it, with a pink lotus blossom on the base of his skull. He has luminous pale eyes, wears no make-up and is dressed in a black hoodie and sweatpants – a Buddha in a tracksuit.

Even as a svelte youth playing on his androgynous looks, he had the suggestion of a double chin, one which he used to disguise with shadowy make-up. Now, at 47, he seems comfortable with himself, but different… different from the man who was once one of the most recognisable people in the Western world, after Diana, Princess of Wales and the Pope. So different that it is possible not to recognise him at all, as Italian police discovered a couple of days before my visit.

‘I lost my passport when I was in Italy and because I didn’t have a driving licence I had to show my credit cards, and when they still wouldn’t accept who I was, I had to do the Boy George thing, which I rarely do. I had to say, “I’m Boy George”, then they let me go. They clocked I had nail varnish on and that caused great hilarity.

‘You’d think people would get over it, but they never do. Look,’ he holds out nails that are chipped and varnished black. ‘It isn’t even proper nail varnish. It’s scuppered and butch. It’s manly nail varnish. In a way, it is reassuring, like police sirens.’

The varnish helped convince the Italian police that he was Boy George? ‘I suppose so. Anyway, they let me go, which was a relief. Thought it was going to be pasta for a week.’

He still does nice lines like that. Indeed, they trip off his tongue relentlessly. He talks quickly and breathily – wheezily, actually, because he suffers from asthma. On the subject of which, he couldn’t have eaten pasta for a week, because he is on a special no-wheat diet. No sugar, either. The asthma doesn’t stop him smoking, though. ‘When you smoke as a singer you lose a few octaves, but you gain something as well. Pure jazz, my voice.’

In a curious way, his voice is more recognisable than he is these days. The cadence is still vaguely East End, still archly camp, or camply arch, and it is still punctuated with laughter – albeit the laughter of habit rather than mirth. He always laughed like that when interviewed on television, but I never realised until now that it was a nervy, defensive laugh. Perhaps it has become so over time.

Boy George was just 19 when he found fame as the singer of Culture Club. The reggae-influenced New Romantic band released their first record in 1982 and went on to sell more than 50 million, notching up seven British and nine American Top 10 hits, and going to No 1 in both countries with Karma Chameleon. Boy George played upon his androgyny not only in the way he dressed – the beaded hair, the geisha make-up, the big hats – but also in what he said. When talk-show host Russell Harty asked if he was keen on sex, he said he’d sooner have a cup of tea.

Actually, he was very much gay, as well Harty knew, and when he did officially come out in America, two years later, he had to wear a bulletproof vest because of the death threats – with admirable insouciance, he worried that it made him ‘look chunky’. Examples of his self-indulgence were legion, but perhaps the most rock-star-ish was his insistence on flying the opposite way around the world to the rest of his band for a show in Japan – because it was better ‘nine ki’ energy.

Despite this better energy, the band split up in 1986 and Boy George checked into rehab for his heroin addiction. Some solo success followed, both as a singer-songwriter and as a club DJ. But his biggest come-back was his autobiographical musical, Taboo, which did well in the West End, and not so well on Broadway. He also launched his own designer clothing label (B-Rude) and wrote a memoir, Take it Like a Man.

He has just started a new tour, his first in 10 years, but it may be cut short depending on what happens next month. George O’Dowd, to use his real name, is due to stand trial in November after being accused of falsely imprisoning a 28-year-old Norwegian male escort and chaining him to a radiator in his former flat in London. O’Dowd pleaded not guilty to the charge in February and was released on bail. He faces a possible 15 years in jail. ‘I would love to be able to talk about the trial but I can’t,’ he says now. ‘I’ll talk to you about it afterwards because there is a lot I would like to say.’

Is he apprehensive? ‘No. I’ll think about it when it happens. You wouldn’t want to think of me spending all these weeks panicking in anticipation. It would be so bad for me.’

He says his spirits are kept high by the fans who come to his concerts, as well as by the people he bumps into in the street. Some may consider his behaviour seedy, but there seems to be a deep-seated affection for him as well. ‘People are funny in England. They will cheerfully shout out, “Hey, George, I hear you got nicked again, you’re a one!” Sometimes it can be annoying, but usually it makes me laugh. In America, no one says anything. They are too embarrassed to bring it up.’

This latest charge follows his arrest and trial in New York. In 2005, O’Dowd falsely reported a break-in at his Manhattan flat – and police officers who responded found 13 grams of cocaine there, allegedly, but their over-eagerness to search without a warrant ruled out the possibility of drugs charges. He was found guilty of wasting police time and a judge made him sweep the New York streets on a five-day community-service order. O’Dowd called it ‘media service’ because of the paparazzi frenzy that followed. With his state-issue orange vest, he wore Capri pants and shoes without socks. It was meant to be a humiliation, but O’Dowd reckoned his working-class background meant it wasn’t. ‘My mum was a cleaner, my dad was a builder,’ he shouted across to the scrum of reporters, as he got to work with his brush. ‘Know what I mean?’

Does he take drugs now? ‘Never, ever, ever do drugs again and I don’t drink either. My job of giving the police something to do is over.’

How long since he took them? ‘It’s been a long time. Telling you exact days and months is only helpful to me, not you. I can say that now and mean it, because I’m in a good place. But there was a time when I could have said it knowing I didn’t mean it.’

A curious distinction. Drugs brought him pleasure to begin with, presumably, but if he had his time again would he take that first line, that first needle? ‘If I had known what a dreary old road it would be? Never. And if I can stop anyone else starting on that road, I will. Time is precious and drugs waste time. I think Amy Winehouse is going to realise that soon. Hers is the most played-out drug addiction in rock’n’roll history. Like a living soap opera. But pain makes a wonderful sound. Her terrible vulnerability is touching. So raw and effortless, not even pushing the notes. From a singer’s point of view that’s scary. You notice she is hitting these rich notes without trying, tossing them away like a handbag.’ Pause. ‘And I love her hair-do.’

He’s sort of talking about himself, of course. And on the subject of soap operas, why did he agree to be filmed for The Madness of Boy George, an unflattering Channel 4 documentary a couple of years ago? ‘They pursued me until I surrendered. It was dreadful. A piece of trash. It’s the worst thing I’ve ever, ever done.’ He laughs at his own exaggeration. ‘No, it’s not. Of course there have been much worse things I have done, and will no doubt do, but as a piece of television it was lazy; trying to turn me into a headline.’

They didn’t have to try too hard. ‘You mean because I was doing the community service when they were making it? Yes, but why did they have to go on about that?’

Well, it was a bizarre episode, even by his own standards. ‘As much as other people might like to cling on to it, it’s over. Done. It means nothing to me, Oh Vienna.’

So he didn’t learn anything about himself from that experience? ‘I learnt that I don’t like getting up at 6.30 in the morning and that Chinese people chop vegetables really small, which makes them hard to pick up off the pavement.’

Does that make him shallow? ‘Oh God, you’re really trying hard, aren’t you? No, there is nothing remotely shallow about me: I could probably talk for hours about my community service, but it means nothing. Nothing. It was only five days. I don’t know whether that makes me shallow, or enlightened and Buddha-like.’

Well, he’s Buddha like in one respect. He even seems to have a shrine to himself in the house: two shelves of curiosities including two wooden name plates: one that reads George O’Dowd, the other, Boy George. We are sitting in his high-ceilinged kitchen, which has stairs leading up to a balcony.

On one wall there is a giant mirror, on another a stencil painting saying, ‘F— you. Hate you.’ There is also a photograph of David Bowie, a crucifix, an assortment of candles and a gothic-looking throne-like chair, whose arm rests are fashioned in the shape of two large phalluses. ‘They were made for me,’ he says when I do a double-take. On another shelf are books about Andy Warhol, Marc Bolan and Oscar Wilde.

It may sound unlikely, but there is something Wildeian about Boy George. He is known for his bons mots, after all – at one point he says to me,’Honesty is a curse. It will get you charged every time,’ which is pure Wilde – but also, like Wilde, and every hero of a Greek tragedy, he seems to have been the author of his own downfall.

He shakes his head when I put this to him. ‘If I sweep the streets that does not mean my life is totally tragic. It’s not who I am and it doesn’t take away from the fact that I sold millions of records. I know the media don’t get that and it frustrates the hell out of me. I think I’m generous because I don’t have a blanket attitude to the media, despite what it has done to me and what it continues to do to me.’

Blimey. Get arrested. Blame the media. ‘I’m not blaming the media for that. What I mean is… I’m letting you into my home. I’m not saying there are any questions you can’t ask me. Try asking Madonna or Sting some of the questions you have asked me, and someone will step in and tell you you can’t. Interviewing me is a luxury and you should appreciate it. I’m an intelligent man. I’m exciting company. You can analyse me all you like, but please do a good job. Don’t be boring.’

Blimey again. And OK, I’ll try. He comes across in print as being pricklier than he is in person. Actually, he is likeable and funny, once you get past the nervous tension and the drama queeniness. But he seems to have little equilibrium, no shame, and no self-control. What he does have is self-pity, self-destructive impulses and delusions of grandeur. He can seem wounded and spoilt, but also, at times, worldly wise. And he is an odd mix of vanity and self-loathing.

Does he feel like a victim? ‘For other people it may look like I was built up to be knocked down, but actually I don’t have that kind of perspective. I was sweeping, now I’m not sweeping. I suppose on the last day I did try to keep my orange jerkin as a souvenir. It was a weird experience and…’ He laughs. ‘Now you are making me think about it!’

But it sounds as if he’s not the sort of person who has regrets. ‘Know what? I have loads. But lately, I’ve been thinking I don’t have to be that person and behave in that way. I’ve never noticed this before in 47 years.’

How has he not? ‘Because there has been too much hairspray in the way. You don’t notice because even when your life is dysfunctional you think that’s normality.’

I begin a sentence about the fame he enjoyed, or endured, in the 1980s, a time when he was one of the most recognisable people on the planet… But he cuts me off… ‘What do you mean “was”? I still am and always will be. Your talking about me as if I’m not here gets on my nerves. I’m here, in your presence!’

Then he redeems himself. ‘I sound like Gloria Swanson, don’t I? Look, no one can take any of that stuff away from me because it’s mine. I’ve learnt to appreciate what I have. My life is amazing. Being Boy George, putting on a hat and make-up, is amazing. And easy. Being George O’Dowd is the f—ing battle. I still moan as much as I always did, but I stop myself now. When things are kicking off, I can tell myself, “You don’t have to do this. You don’t have to be nasty, you don’t have to be an a—h—.”‘

I mention that he seems to have a lot of anger just below his surface. ‘I come from a family that explodes. Mine is the great exploding family.’

Does he enjoy exploding? ‘Actually, I don’t. I don’t find it therapeutic. I’ve come to realise that when I snap at people they get hurt. When you care about someone… which is the difference. I care if it is someone in my family. When it’s someone from the record company it doesn’t mater if I shout, Yahhhbllagghh!!! at them.’

Record company executives don’t have feelings? Or is it more that he doesn’t care if they do? Isn’t that a little selfish? ‘You’re trying to narrow me down to a headline aren’t you? Yes Boy George was selfish, but he’s not now. I was a b——, but I recovered.

‘I need to go out and perform to the people who always forgive me for everything I do and that is the Great British public, God bless them. I go out there and feel so lucky. They still sing along with my songs.

‘To be honest, when I started this tour, I thought: “Who is going to want to come and see me after all this time?” But when you get to Norwich and Newcastle, I mean, all these weird people come along to see you, all these old ladies who dance and sing along to Karma Chameleon and shout [he adopts a Geordie accent], “I f—ing love you George.” In Northampton, there were all these stage-door hangers-on and they were my mum’s age; it was really sweet and really funny. I’ve become Barry Manilow!’

He can laugh at himself, and that is his redeeming feature. As well as being a builder, his father, Jerry, was a boxer, one who used to beat up his wife. By wearing make-up as a teenager, George was rejecting his father’s masculinity, clearly. But he may also have begun wearing black lipstick to get his father’s attention (he was one of six children, after all).

He still craves attention, which may partly explain his almost Tourette’s-like tendency to insult people. ‘It sounds like a name-drop, but Elton John rang me up the other day and it was really exciting,’ he says. ‘Elton John has my number! I had a barney with him a couple of years ago and I loved the fact that I had pissed him off [he had called him a ‘humourless grand old dame’]. I can’t believe I’ve registered with him. He was fuming, “I’m going to kill that Boy George!”‘ A result.

Does he fall in love easily? ‘I fall in lust easily, but I don’t think I’ve ever been in love. I look back and think was that love? But I’ve never been in that stage where I think I don’t want anyone else.’

According to his memoirs, his longest relationship was with Jon Moss, the drummer of Culture Club, who is now married with children. He wrote the band’s first hit Do You Really Want to Hurt Me about Moss. (Actually, it was the other way round. Boy George would throw bottles at Moss and once broke his fingers.) I ask if Moss was the love of his life. ‘I thought so but, with hindsight, I’m not sure he was. He was certainly the great drama of my life, but I’m not sure I love him more than I love my mother. No, I definitely love my mother more. Was it love? I cried. He punched me. There was music.’

Was he ever beaten up because he was gay? ‘By my own brothers. By kids at school, every day from the age of six they would shout “poof” at me. School was a hellhole.’

Did he ever fight back? ‘I can fight but I don’t like fighting. You scratch your nails.’

What about ‘muscle Marys’ such as Rupert Everett: gay men who work out? ‘I’m much tougher than Rupert Everett. I could knock him out in five seconds. Muscled men are the most scared because they are building a wall. We are the only culture who identifies with our persecutors, gay men trying to act straight. The toughest ones are the drag queens. They are the suffragettes. They are the warriors. You ain’t a man till you’ve walked in heels.’

John, his business partner, arrives for a meeting and George asks him if he will do him a favour and go out and get a packet of cigarettes.

‘You’re vile,’ George says.

A few minutes later the buzzer sounds again. It is someone called Lady Pat, a man, who is also expected at the meeting. ‘Do you smoke?’ George asks before buzzing him in.

‘No’

‘I hate you’

J.

James Blunt

It could be the homes around the world; his military bearing; or that he’s our biggest musical export since Elton. For whatever reason, being called annoying, a philanderer or – worse – middle class doesn’t exactly keep James Hillier Blount awake at night. Nigel Farndale met him

It’s not the sight of the groupies that haunts me, but the sound, or rather the absence of sound, as they ghost past us on their way up the stairs to the dressing-room. It takes me a moment to figure out that the reason they aren’t talking to each other is that they don’t know each other. One of the band members, the keyboard player, I think, has picked them from the audience on the basis of their looks. Half-a-dozen of them, all in their late teens and early twenties, and all, surprisingly, in pretty frocks, as if they were going to a Sunday school meeting. They have been separated from their friends like lambs weaned from their mothers. The silence of the lambs.

The ‘us’ they are filing past is James Blunt and me. He has a bottle of beer in one hand, a cigarette in the other, and not a hair in place – tousled just so, like a Renaissance painting of John the Baptist – but they don’t realise it’s him because he has changed out of the suit he was wearing on stage and is now in jeans, T-shirt and leather jacket, as well as a pink feather boa and star-shaped novelty sunglasses. But I’m getting ahead of myself. This is the end of the day; we need to go back to the start, well, to the middle, when the seats are empty and the Texan sun is at its most unforgiving.

A barefoot and unshaven Blunt is wearing normal sunglasses and shorts as he plays his piano, strums his guitar and sings his plaintive songs into the microphone for the sound check, all the while looking out with his soulful eyes over an empty, open-air arena in Houston. At 5ft 7in, he’s not a tall man, but he has presence and an unaffected manner – a certain maturity, too, one that you wouldn’t normally associate with a pop star in the ascendant.

But then he is 34 and this is his second career, his first being as an officer in the Household Cavalry. He joined after graduating from Bristol University with a degree in sociology. He became a champion skier for the Army and not only saw active service in Kosovo, but also guarded the Queen Mother’s coffin when she was lying in state.

Tonight he will be supporting Sheryl Crow, though, since his second album ‘All the Lost Souls’ and the single from it, ‘1973’, went straight to number one in America, he is arguably the bigger act these days. Indeed, not since Elton John has there been a more successful British singer-songwriter in the States.

His first album, ‘Back to Bedlam’, also went to number one over here, as it did in 18 other countries, making it the biggest-selling album of the millennium. It even entered the Guinness Book of Records as the fastest-selling album in one year. But it was his first single that really put him on the map. You’re Beautiful became the sound of that summer. It was everywhere, and still is – having become a favourite at weddings, funerals and bar mitzvahs. I even heard a brass band playing it at an agricultural show in the Yorkshire Dales this summer.

As well as millions of sales, James Blunt has won Brit awards, Ivor Novello awards, MTV awards and various Grammy nominations. In terms of credibility, he’s headlined at Glastonbury and won the respect of the world-weary music press. Yet not everyone loves him, as he points out when we get something to eat in the canteen area back stage.

‘After Back to Bedlam really started selling,’ he says, ‘there was this sudden aggression towards me in the UK, for whatever reason, and that focused my mind, made it clear to me what I was doing and why I wanted to do it. I write songs for myself. I don’t write them for you, or for anyone else, I write them because I have experiences that I need to process. I don’t have the answers all the time, but I do have lots of questions, and I express them in the songs I write.’

He is, I think, alluding to a poll last year of ‘the most annoying things in life’, which put him at number four, just behind cold-callers and queue-jumpers. ‘I haven’t met anyone who voted in the poll, have you?’ he says when I mention this. ‘That poll probably came from a website that was after some publicity. You and I could do the same poll very quickly right now and it would count as a poll. We could do one about annoying newspapers, for example. I promise the Sunday Telegraph wouldn’t be in my list. My parents take it.’

His father, a retired colonel in the Army Air Corps, manages his son’s finances. His mother arranged the purchase of his six-bedroom villa in Ibiza (he also has a chalet in Verbier and recently bought a place in Chelsea). ‘I’m not married,’ he says, ‘and so the support structure in my life is my parents. I’m closer to them now than I have ever been.’

He certainly isn’t married, as the photographs of him emerging from nightclubs with various high-profile women on his arm attest. Tara Palmer-Tomkinson was probably the best known socialite, Jessica Sutta, of the Pussycat Dolls, the most glamorous. He also seems to be photographed regularly cavorting on beaches with bikini-clad models such as Petra Nemcova, whom he dated and then dumped – unceremonious dumping being his way of ending relationships, according to the tabloids. He once said he found himself in a swimming pool in LA with nine naked women. ‘I was the only bloke. It was the only time I wished my mates were there, purely to spectate. I had arrived. It was a moment.’

Now he says of the tabloid interest in his peripatetic love life: ‘Last week I went to my home in Ibiza and was photographed by the paparazzi in my swimming trunks with girls. What is the point of that? I’m not that bothered, but maybe the media should be concentrating more on global warming or the Russian invasion of Georgia.

‘Looking at me in my swimming trunks is not a great sight. It’s a waste of time. There generally is a long lens pointing at me wherever I go, these days. I’m comfortable with it. I appreciate how things work. But my record label said something about my always being photographed coming out of nightclubs and I thought, “But this is what I do. I was doing it before the second album came out, so what is different now? You didn’t tell me to stop then.” I’m not going to change my life because of these people. I don’t see why I should.’

His label also gets him to dye his grey hairs and be enigmatic about his love life, which is an old tactic dating back to the Beatles – they had to pretend they didn’t have wives and girlfriends so that fans could fantasise they were in with a chance.

Actually, at the time of going to press, Blunt seems to be going out again with one of his old flames, Verity Evetts, an Oxford-educated barrister. He has also stayed friendly with some of his other exes, the socialites at least. He told one – an ex who got married not long ago – that he doesn’t feel ‘centred’ at the moment and would like to get married as well. Then again, he also said that he never tires of singing You’re Beautiful night after night because it gets him laid night after night.

Either way, he tells me he has grown used to the idea that his mother will probably find out from the papers what he has been up to, and with whom, before he has had a chance to tell her. ‘And my [two] sisters are quick to email me about things in the papers, laughing their heads off. I get healthy, ritual abuse from them, and give it back myself.’

As we are talking, I can’t decide whether the way Blunt smiles all the time is disarming or disturbing. He’s like a victim of a religious cult, smiling at the beginning of the sentence and at the end. I guess he has a lot to smile about, but also I sense a great deal of insecurity to disguise.

Then, I’m distracted by the sight of Sheryl Crow playing table tennis across the room. She has been holding her adopted son in one arm as she bats with the other, and now, even more distractingly, she is heading straight for us. ‘Are we going to have one of our little conversations on stage again tonight, James?’ she says. ‘That flirting thing. I think it worked well last night.’

They discuss the duet they will sing – a cover of Cat Stevens’s The First Cut is the Deepest – then we both watch her shimmy away, her blonde curls bobbing. ‘She’s very down to earth,’ he says. ‘I’d met her a couple of times, which was why she asked me on this tour. We do end up playing a lot of table tennis on the road. We’ve done 117 shows so far this year, in 117 cities, and there are a lot of hours to fill in the day.’

As he sleeps on his tour bus with his band, one city tends to blur into another. When I joke that he is in Cincinnati now, he looks genuinely confused. ‘No, this is?… Oh, right. Actually, I always get the tour manager to say where we are just as I’m going on stage. I still managed to get it wrong the other night, saying “Hello Dallas” when I meant Austin. I’m surprised I got out alive.’

He is funny on the subjects of things that go wrong. ‘People are normally surprised by my show, which is more energetic than you might think. Jumping on the piano. Jumping out into the audience and running up and down the aisle high-fiving them. But going off the stage can be quite dangerous. I broke my finger once. My legs carried on when I jumped off, and I smacked down on the ground. The spotlight was on me, and when I got back to the piano I hit the wrong note and thought, “Why did I do that?” And I looked down and saw it was because my finger was broken, sticking out an angle. Look,’ he says holding it up. ‘It’s still crooked.’

On another occasion, in Chicago, he jumped 8ft off the stage. ‘When I began running to the audience, a security guard stuck his arm out and I thought, “Does he want a hug?” Then next thing I know he’s rugby-tackled me. He wouldn’t release me and I was screaming in his ear, “I’m the f—ing singer.” I had to wait for the other guards to pull him off.’

I would have thought Blunt’s training in unarmed combat would have helped. I presume he still works out. ‘No, never. Couldn’t handle it. Too boring. I am a hyperactive person though.’ He likes an adrenaline rush, as well, having recently bought an 1100cc Moto Guzzi V11 Sport motorbike. There’s also the skiing, which he still does, and the riding. Actually, he tells me, he never really liked horses before joining the Life Guards. So why did he join that particular regiment?

‘Well, it is a reconnaissance regiment.’ But they are all so tall in the Life Guards, did that not make him self-conscious? ‘Some are. The Foot Guards tend to be taller regiments, though. The Life Guards take a few shrimps, as well. Besides, they are on horses, so height isn’t so important. Also being in that regiment had the benefit of being in Knightsbridge. I got a chance to be in London and meet people in the music scene.’ And groupies, as it happens.

As he paraded up and down the Mall in plumed helmet and shiny breastplate, girls would stick their phone numbers down his knee-length boots. But it was his time in Kosovo that really made girls swoon. He used to strap his guitar to the outside of his tank, because there wasn’t room for it inside. He had learnt to play the violin at five, the piano at seven and the guitar at 14, while a pupil at Harrow.

He writes his songs on piano and guitar. ‘But mainly guitar because it is easier to carry around. It’s like a child messing around with a toy. If a tune comes to me I don’t record it instantly. I think if I remember it, then it must be worth remembering, and if I forget it, then it was forgettable.’

Does he have any anxiety dreams about forgetting lines or chords? ‘Not yet. Perhaps I will tonight. Perhaps you’ve jinxed me. But audiences aren’t judgmental, and if things go wrong and you can look them in the eye, that is fine. The only people who are judgmental are the journalists. I will be conscious of you being there in the audience judging me.’

Blimey. Sorry about that. Is it true he signs breasts? ‘Not that I remember. Not that I’m fussy what I sign. A lot of men started coming to the shows after I appeared on Top Gear last year. That was such fun. I spun the car five times. I thought I might as well make the most of it. I am competitive.’

He recorded one of the fastest laps, but I’m surprised blokes didn’t think him manly before that, given his tour of duty in Kosovo. ‘It’s because I sing songs that are heart-on-your-sleeve and therefore I must be overly emotional. Nothing I can do about it. I could pose more, but I am comfortable with my masculinity.’

He has said that his lyrics are autobiographical, in which case, are we to assume that the lyric on his new album, ‘I killed a man in a far away land’, means he killed a man in a far away land? I only ask because in the past he has said that he would never try to exploit what he went through, what he saw. ‘You should ask any soldier how many lives he has saved. How they do it is no one else’s business. What I took from my experience in Kosovo is that you are told from one day to the next who your enemy is and it keeps changing. That’s what is happening in Iraq, too. I believe in looking people in the eye, looking for the common humanity.’

He is a great believer in looking people in the eye. He will use the phrase again later and it seems to reveal a Christ complex, or a John the Baptist one. That direct and challenging stare of his. It would also explain the hair.

It is time for him do some photographs before he goes on stage and, endearingly, he says he is ‘not fussed’ about the grooming he is offered before they are taken.

On stage his features contort with passion when he sings. The big video screen goes in tight on his face. His voice is by turns soft and tremulous and forceful, but always high. Having seen him in concert once before, a couple of years ago, I notice the tone of his banter has changed.

‘Wow it’s hot tonight,’ he says now. ‘I’m surprised any of you are wearing any clothes. We could all take them off and get friendly.’ It is suggestive, designed to get the teenage girls in the audience screaming. Before he used to joke about his ‘girlie voice’ and taking helium to get it that way, and being ‘a bit wet’ and the ‘housewives’ favourite’. I think now he has realised that, actually, he is a proper musician, a popular one, too, and that he doesn’t need to apologise for it.

Afterwards, back in the dressing-room, he strips to the waist as he talks because he wants to take a shower before going back on to do his duet with Sheryl Crow. ‘Things got a bit hairy out there when I jumped into the crowd,’ he says. ‘Did you see that? Some thought it was some kind of sport to grab me.’

I watch his duet from the side of the stage and notice he whispers something in Sheryl Crow’s ear and then she starts running her hands over his trousers suggestively, patting them. Afterwards, I ask what he said. ‘”Is now a good time to ask for your phone number?” She was checking my pockets, pretending to look for a pen.’

He shows me round the gold-coloured tour bus where he will be sleeping tonight as they drive to their next gig in Dallas. It is full of hi-tech equipment and is nicely air-conditioned but there isn’t much space in the bunks. ‘We do live in close proximity,’ he says. ‘Some of us stay up late. This is the crew end, they have to get up early.’

Where do the groupies go? ‘Never have groupies on here. Never. They’d only get in if we invited them in. But we’d only ever invite friends in.’

Does he sleep OK? I heard he has to take sleeping pills. ‘It is a bit of a rough sleep, but better than a hotel and taking planes all the time because you have to get to the airport two hours early, which is miserable. Then your flight gets delayed.’

He is drinking champagne from a plastic cup. ‘This is for your benefit,’ he says. ‘The tour management went out and bought a bottle of champagne because he thought I should be seen drinking it. Better for my image. Isn’t that sweet? Normally, we drink vodka and beer. In fact, I think I’d rather have a beer, now. Want one?’ He opens a well-stocked fridge then takes me to the back of the bus where there is some seating space. He has one small case which he pulls out from a cupboard. It continues a few pairs of socks, T-shirts and a spare pair of jeans. No photographs or mementos. ‘This is all I have for 14 months on the road,’ he says. ‘I’m not known for style.’

Does he know how much he is worth? ‘No I don’t, not very interested in it to be honest. I travel with hand luggage only. That is why I always seem to be wearing the same clothes in photographs. If a tabloid says my clothes aren’t fashionable or my hair looks stupid, I really don’t worry about it. Don’t have any hair gel.’

In London, he takes the Tube or the bus. He prefers pubs to restaurants. When he goes to Ibiza, he flies easyJet. Still, that’s at home. Presumably on the road he can afford to be more self-indulgent.

Another lyric that we can only assume is autobiographical is ‘I’ve taken a s—load of drugs’. It is. Though his only comment on the subject is that he has ‘a comfortable relationship with drugs’. His relationship with fame is less comfortable. Oscar Wilde said there were two forms of tragedy: not getting what you want, and getting it. Is that how it felt for him when he went to number one? ‘Actually, I don’t think I had been dreaming about it. Certainly, I hadn’t anticipated being so recognisable so quickly.

‘I do remember getting a phone call from the record company, who said both the single and the album have gone to number one, and thinking, “S—, this is not what I expected.” I hadn’t prepared myself for it. Number two is great. Number two is nice. I sensed then it would mean having to change from being a musician to being a celebrity and that that would be a change for the worse. Fame doesn’t affect me, but it does affect everyone else around me. As for celebrity, it is the worst invention of the modern world. Gossip columns treat your life as if it were a cartoon. Relationships reduced to cartoons.’

Although there are other public-school bands around at the moment – Radiohead, Coldplay – Blunt seems to have suffered more than most from a perception that he is too posh to be credible. His family name is Blount (and his middle name Hillier), but he changed it to Blunt to sound, well, blunter and more proletarian.

When he tells me he would nevertheless still send a son of his to Harrow – ‘I think I would. I think I would. Public schools make individuals rather than sheep’ – I ask what he makes of the mood change now that the old Etonian David Cameron has made it OK to be posh. ‘Is it? I must come back to Britain immediately. Is it really safe to come back?

‘It’s not a dirty word to be posh, people come up to me and no one gives a damn if I’m posh. It’s about having a normal conversation and looking people in the eye.’

We head back to the dressing-room where he puts on his feather boa and novelty sunglasses then we wander back downstairs to have a word with Sheryl Crow, who is signing autographs. This is the moment at which the keyboard player says: ‘This way to the good-time room girls’ and the silent groupies dutifully appear.