Boy George, one-time sage of the groundbreaking band Culture Club, is back . . . and, after a troubled year culminating in a spell sweeping the streets of New York after a cocaine bust, the famously outspoken singer is angry.

In a withering attack on fellow stars, he goes on to describe Madonna as "vile" and Elton John as a boring role model. Robbie Williams' music is dismissed as "terrible".

The singer also reveals that, despite his profile, he is a regular user of gay prostitutes and tells of how he lost himself in a blur of cocaine, which saw him conducting imaginary conversations alone in his apartment.

Boy George (45), the son of Irish parents, has spent much of the past 12 months wrestling with personal issues after being arrested for cocaine possession at his New York apartment. He was eventually ordered to serve five days community service in August of this year, in a very public humiliation which saw him hounded by TV crews, photographers and reporters as he swept gutters in Manhattan.

Now, in a new Channel 4 documentary, he proves he has lost none of the power to shock by rounding on numerous celebrities.

His choicest venom is reserved for Madonna. In an extended rant, he splutters:

"Madonna. . . euch. I just think she's a vile, hideous, horrible human being with no redeeming qualities. There's nothing nice about her, I've never heard anyone say anything nice about her at all. And anyone that's ever met her she's been vile to. Vile, full of herself . . . so unspiritual. How has this woman got away with it for so long?"

For the new documentary to be broadcast on Tuesday, Boy George let cameras follow him for four months, allowing them into his east London flat, which he has decorated with self-produced homoerotic artworks. His bed linen, taking a cue from Tracy Emin, is decorated with the names of some of the people he has slept with, including his former long-term love Jon Moss, the drummer of Culture Club.

When his fame was in its infancy, Boy George was reluctant to admit his homosexuality and he famously declared that he preferred "a nice cup of tea to sex". In reality he was in a relationship with Moss, but few were surprised when he eventually admitted he was gay. Now he is "militantly" so.

He also admits to using the internet to trawl for partners and paying for sex. "Straight people have been doing it for years. Prostitution is the oldest, most respected profession. I don't think there's anything wrong with it. . ."

In the mid-1980s, after his chart success started to slip, George turned to heroin like others in his social scene. His brother David went public about his drug use to shock him into action.

Fined for a possession charge, he cleaned up his act for almost two decades, but sunk back into drug use following the savaging of his stage show Taboowhen it went to Broadway, culminating in his bust last year. He had called police himself, believing there had been a burglary at his flat.

"It got to the point where I lost all sense of reality. I think briefly before I called the police I was talking to a photograph, and it was talking back to me, " he admitted.

"I let the police into my apartment hoping that they wouldn't search it, but they did. They found a little bit of cocaine in my bedroom, it certainly wasn't as much as they reported."

His experience in police custody was unpleasant: "The police were so, so hideous to me, so unkind. They wouldn't give me water. I ended up drinking my own urine. I had a tannoy, a speaker on me, just insulting me for about nine hours calling me 'faggot', you know, 'a useless f***ing hasbeen'.

"I remember towards the end of it just being on my knees in a jail, wanting to kill myself. " Although he calls his punishment "a media service day, not community service", he is upbeat about the experience of street sweeping. "I quite enjoyed working with the people, I've enjoyed the interaction, and it's quite grounding.

I've enjoyed it, in a bizarre, perverse Boy George kind of way."