I can’t say I was looking forward to meeting Boy George. Those photos of him two years ago, bloated, brutish and sinister; the arrest for imprisoning a Norwegian man in his London flat, manacled to the wall and to the bed, and beating him; his own jailing for the crime. He had become so unrecognisable that it was hard to believe he had once been the pretty and effeminate singer with the massively popular Eighties band Culture Club. Stars lose their looks, from Elvis Presley to Adam Ant, but there never was such a dramatic morphing as this, all the way across the spectrum from beauty to beast, sweet little thing to nasty piece of work.

For days before our meeting, the negotiations were dogged by the tedious rock’n’roll foreplay that often happens on such occasions. Boy George, said his representatives, did not want to talk if the whole thing was going to be about “my prison hell” (their phrase). He served four months of a 15-month sentence, until May this year, in HMP Edmunds Hill, a category C prison in Suffolk, and then wore an electronic tag for a further three. He is, in a word, out, and back in the public eye, if he was ever truly away. He has product to shift, namely himself and his new moves in the entertainment business – the imminent opening of a no-booze, no-drugs club called Godspeed, the return of his West End show in December and a live performance at the fashionable Proud Camden in London.

When we do meet, it is in the old stables that form part of Proud, a gallery cum music venue, where the matter of his crime and punishment stands like an elephant in the stall. So it’s a surprise when he says: “The thing about Pentonville [where he spent the first six days of his sentence] is that when you go in there, you are going into Scum [the violent 1979 film about life in a borstal]. You’ve got the classic picture of the balconies and the banging cups. I knew what to expect. I was quite hostile.” Hostile to the other prisoners? “Yes. Very hostile. And very grumpy. Not because I felt that way particularly, but because I felt it required that. The situation required me to be a bit feisty, a bit don’t-f***-with-me. I’d heard it all before. I’ve grown up with all that name-calling. I can’t walk down the street without someone calling out, ‘Karma chameleon.’ [Culture Club’s 1983 hit single.] That’s sweet; that doesn’t bother me.”

The 48-year-old singer hasn’t spoken publicly before about his prison experiences, but he is so quick off the mark in doing so now that there’s barely been time to take in the present look of the man. Something’s changed. He was always a chameleon himself, a professional one like his idol David Bowie, but the alteration in him looks far more profound than a shift of image. He cuts a very different figure now to the one on display at his trial and conviction at Snaresbrook Crown Court in December last year. He’s lost weight: he looks firm, and astoundingly solid. It’s more the set of a builder, which his late father was, than of a New Romantic, however middle-aged. He carries himself like someone who reckons he’s useful. But it’s in the face that the big change has happened. That awful frame of raddled flesh has fallen away to unveil the old androgynous expression of the young Boy George: hard little imp. His eyes twinkle with a weird but rather benign mischief, and there are times when he can barely talk for overjoyed laughter.

So this is why he wouldn’t talk of “my prison hell”. There wasn’t one. A nasty little time in Pentonville perhaps, where he wore a T-shirt with a glittering handcuff design and, according to one source, needed a minder because he was scared and disorientated.

But at Edmunds Hill it was a different story, and this is how he tells it: “I felt strong throughout the whole thing because I knew there was a beginning and an end to it. So for me it was a matter of, OK, so this is how long I’ll be here, what am I going to do with the time? I read everything I could. I read Bleak House, The Catcher in the Rye, The Ginger Man, A Confederacy of Dunces. I really identified with the central character of Ignatius J. Riley.” The Southern US novelist Walker Percy described Riley as, “A slob extraordinary, a mad Oliver Hardy, a fat Don Quixote, a perverse Thomas Aquinas rolled into one.”

One of the books that made the deepest impression on him was The Thief’s Journal, Jean Genet’s largely autobiographical novel about the roamings and incarceration of a homosexual prostitute. “I found that very erotic, and I kept thinking, well, I won’t be able to pass this one on.”

As he talks like this, one elephant, the prison one, leaves the room, but another appears in its place, arriving trunk-to-tail.This is the question of remorse for a nasty crime. There is the familiar danger of a redemptive tale like this upstaging everything else – the consequences, the victim’s life, the contrition (or not) of the offender. In the course of the trial, the court heard how Audun Carlsen, a 29-year-old male escort, was manacled by the singer and another man for several hours, eventually managing to escape and run from the Shoreditch flat wearing nothing but boxer shorts, trainers and a pair of handcuffs.

The singer, whose real name is George O’Dowd, was by his own admission under the influence of cocaine. Indeed, he now says that he was rarely not under its influence for a five-year period that encompassed the incident, and came to an end about 20 months ago. He rattles off the starting date of his present abstinence – “March 2, 2008” – adding with triumph that 15 days have passed since his most recent cigarette. But the British courts are adamant: a drunken (or stoned) intention is an intention nonetheless.

Where is his remorse? We come on to this in a moment, and his reply is unexpected. But he has not quite done with prison. He says he was never physically afraid. “If anyone bothered me, I’d have hit them back, no problem. They would have got what they gave me. What people don’t realise is that bullies aren’t popular in prison. If you have someone ringing the alarm, then everyone gets locked up, like school. Someone does something wrong and you’re all blamed…” Like a working-class counterpart to Jonathan Aitken, who said jail held no fears for an old Etonian, O’Dowd says Eltham Green School, one of London’s first comprehensives, was pretty good prep for life inside: “Hideous place. Hideous place.”

The low point, he says, was being away from his family and friends. He is one of six children – five boys and a girl – with several nephews, nieces and godchildren. None of his own, however. “Ooo no,” he winces. “I leave that to the professionals.” His parents, Gerald and Dinah, came from Thurles in County Tipperary, and raised their family in southeast London. “While I was away,” he goes on, “I got so many letters from friends. Maybe some of them I had taken for granted, or thought, well, I wouldn’t call your name if I was drowning. They blew me away, it was really beautiful. That was the only time I ever got emotional in prison. I got about 15 cards a month from one of my friends, Dusty. My therapist Jamie, who now lives in Karachi, he told me, during all that turmoil after I was arrested in New York [for falsely reporting a burglary], he told me I had a public responsibility, and if I don’t like it, tough. I remember at the time being really furious that he said that to me – I thought, how dare you. I bumped into him at Heathrow a year ago and he said, ‘My God, you are clean,’ and I said, ‘You remember that thing you told me. I wanted to kill you but now I get it.’ I have a responsibility and that’s OK. It’s not something I should be embarrassed about.”

What then should he feel about the crime that got him jailed? Remorse, surely. Isn’t that what we want to hear before we too can move on from it? The good humour vanishes from his eyes and he says tartly: “I’m not going to talk about that. I’m not going to talk about that.” His face seems to lock up, although he denies that it is. But why no expression of regret? “The important thing,” he says, “is that I don’t feel malice towards anybody. That’s the most important thing. Whether I feel remorse or not is irrelevant. What I would say is this: what happened in the last five years of my life [that is, until he gave up cocaine] was all to do with drugs. I took responsibility for that, in a way. Generally, my attitude is, I put myself in those situations because of drugs. I never would have made those decisions if I had not been high. So that, if I sit down and start thinking about the finer details, I would drive myself crazy.”

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