Ozzy Osbourne in 2002: "I'm the working-class hero – not bad for a guy from Aston"

Security is strict in the Beverly Hills street, off Sunset Boulevard, since the bizarre inhabitants of number 513 became the most sensational family on American television, outperforming Sex and the City in the ratings and winning an Emmy last month for outstanding reality series.

The unlikely focus of The Osbournes is the family of a Birmingham-born heavy-metal star, the self-styled "Prince of Darkness", lead singer with Black Sabbath until he was fired and went solo in 1978, amassing an alleged £40 million fortune.

Now Ozzy Osbourne's a shuffling testament to the ravages of alcoholism, drug addiction and indiscriminate sexual adventures. The interior of his house is mock Gothic – cherubs, stained-glass windows, crucifixes. Pictures of the family – wife Sharon (his manager), daughters Aimee, 18 (who declined to appear in the first series: Sharon says, "She’s the only sane member"), and Kelly, 17, and son Jack, 16, are arranged on a hall table.

Photographs of dogs and cats line the circular staircase, with crosses on them. Such an animal lover, you might think, particularly when you watch him on TV stumble around trying to save a herpes-ridden cat from coyotes. Perhaps it’s an attempt at redemption – he once shot 17 of his cats in a drunken rage.

He greets me wearing black tracksuit bottoms, T-shirt, crosses on gold chains round his neck, rings, including one with a Union Jack motif, and OZZY carved with a needle and lead from a pencil on to the fingers of his left hand when he was jailed for theft in his adolescence.

His arms dangle by his side, fingers trembling, voice slurred and stuttering, myopic behind his round blue sunglasses, hearing impaired by years of decibel excess. His white hair is dyed shimmering black, pulled into a ponytail with auburn ends drifting on to his stooped shoulders.

"I have attention deficit disorder," he warns. "I’m on medication, which helps. Without it, you wouldn’t know what I’m talking about. It’s difficult for me to stay in one place."

I have omitted eight obscenities from those 28 words. The family uses variations of the "f" word every 19 seconds, a relentless repetition that shocks at first, but soon dulls the impact. "Jesus," says Sharon, "we never realised how much we swore."

Such is Ozzy’s popularity that President Bush invited him to dine at the White House last year, and he was introduced to the Queen after performing at July’s Golden Jubilee concert at Buckingham Palace.

"I was freaked out. I assumed I was the in-house joke. I’m my own worst critic. I don’t think I’m good enough for them, for you, for anyone. The Queen spoke to me, but I haven’t a clue what she said. Look at photographs – I’m in shock. I hyperventilate opening a box of chocolates. I’m the most nervous guy in the world, a frightened little man, on red alert from when I wake until I go to sleep. I was born with fear."

What of? "If! I could answer that, I’d save a fortune on therapy. Sharon says, ‘You’ve got the number-one TV show, a sell-out Ozzfest summer tour [which she started in 1996 and made one of the world’s most successful touring rock shows], everyone loves you – and you walk out into a blue sky and aren’t happy until you find a cloud.'

"It’s true. I want to lock myself in a room. I don’t go out much. People have a mental picture of me because this whole business is run on rumours – Ozzy eats bats, Ozzy drinks urine. They read I’m crazy, a drug addict, alcoholic and don’t give a f*** for anyone." He pauses. "That’s true, but I don’t take myself seriously. Performing is like being schizophrenic. On stage sometimes I’m out of control."

Poignantly, Sharon was diagnosed with colon cancer in July, a few days before she negotiated a £13 million deal for a second series of The Osbournes. The cameras will film her progress, although she jokes, "How many chemo sessions can you show on TV? I think it will help women. I had no idea we got this form of cancer, so there must be a s***load of others who don’t realise. I had my 50th birthday recently, and I love my age. I fear death terribly at the moment because my babies are not settled. I want to see them married before I go. I’ll be there with my borrowed diamonds."

Unkind souls suggest the show is less the lurid voyeurism of a real-life Addams Family, Munsters and Simpsons rolled into one, and more a shrewdly marketed pension plan for an over-the-hill celebrity, whose family play to the camera, with Sharon, as co-producer, influencing the content. But Ozzy’s so spaced out it’s impossible to believe his portrayal is anything but natural.

Sharon says that it’s "an understatement" to say they’re surprised by the programme’s success. "We didn’t know it would change our lives. It’s caused my kids a lot of problems. Jack was tearful every day. He didn’t like being recognised with his mates, read unpleasant things on the internet, and thought he’d never be taken seriously, but the good outweighs the bad."

She kisses him goodbye. "He’s going for an interview for a Ben Affleck movie. Kelly made a record [a cover of Papa Don’t Preach] and now she’s like, ‘Mum, I don’t know if I can handle this. I want to hang out with my girlfriends.' Unfortunately, she’s committed to deliver."

Ozzy’s watched less than half of one episode, he says. He doesn’t need to see more. He was there when 50 cameras around the house filmed 24 hours a day for months, capturing, for instance, his astonishment when Sharon hires a pet therapist after one of her numerous small dogs pees on the furniture.

"I don’t think we’re ‘normal’," she says, "although no family is what they pretend to be. There’s always stuff under the carpet, but we all love each other very much, are tolerant, know our faults and get on with it. Ozzy is funny and so honest, I don’t know anyone in the public eye who’d allow themselves to be filmed in underpants, half-pissed, with his belly hanging out. Today’s stars have no character, and put on this false front of being perfect."

They can’t be accused of that. Kelly discusses the hygienic aspect of thongs. They throw a ham and stink bombs over a neighbour’s hedge because they’re making too much noise singing folk songs. "Ozzy Osbourne with his tattoos, scars and long hair is not your typical Beverly Hills person," Ozzy explains to me, straight-faced. "They don’t invite me to Christmas parties, but I wouldn’t want to go. They’re pompous dickheads."

A main attraction is his sweet-natured bewilderment at normal family life writ large. At its heart it has honesty and mutual affection. "I love you all," he exclaims. "But you’re f***ing mad." He tells me, "The kids use bad language, but so does the rest of the world. They’ve been with us on the road, and in rock ‘n’ and roll swearing is the language. Sharon and I have never been parents to go ‘coochy coochy coo’."

The only time he shows petulance is when discussing the bat incident, which took place 20 years ago in Des Moines, Iowa, at a time when he and his audience threw offal at each other and he bit the head off a bat, thinking it was rubber – two weeks of painful rabies injections followed. "My epitaph won’t be Ozzy Osbourne, the man who sold X million records. It will be the man who bit the head off a bat. It’s, like, get over it, man."

The day we meet he’s been told he’s a grandfather. His estranged daughter, Jessica Sunshine, 30, has given birth to a girl Isobel. "Me, a grandfather. Hah!" he grunts. He and his first wife, Thelma, also have a son, Louis, 26. They divorced in 1979.

"Divorce knocked the s*** out of me for years because I can’t stand rejection. I felt like a failure," he says. "I don’t go to England often. I have properties there [a home and 188 acres in Buckinghamshire]. Huh! That makes me sound a big-headed dickhead. I love England – if only you didn’t wake to that drizzle. I came to America in 1976 because there’s hereditary dyslexia in my family and not many English schools cope with that. One thing success has enabled me to do is give my kids a good education."

The fourth of six children born in Aston, Birmingham, Ozzy was always a little eccentric – he stabbed his aunt’s cat at the age of 11 and tried to set fire to his sister. After leaving school at 15, he worked in an abattoir, became a petty thief and was jailed when his father, a night worker in a tool factory, refused to pay his fine.

He was "saved" when he co-founded Black Sabbath in 1968, beginning a decade of addictions – four bottles of brandy a day, and so much cocaine that when it ran out he snorted a line of ants by mistake.

He was arrested, and banned from Texas (President Bush’s home state) for urinating on the Alamo while wearing a woman’s dress. In 1978 he was kicked out of Black Sabbath as a washed-up druggie, and spent six months in a hotel room drinking, snorting and, if he could, copulating.

He was rescued by Sharon, whose father, Don Arden, had managed Black Sabbath. She pulled him from the gutter, never tried to change him. "I was an old tart. I’d drink and take drugs with the best of them," she says, although she says she stopped when she realised one of them would have to settle down.

They married in 1982, and it can’t have been easy. Seven years later he was arrested for trying to strangle her. Once, forgetting she was on tour with him, he returned to his Tokyo hotel room with a groupie.

"I was out of control and didn’t give a s*** whether I lived or died," he says. "I’m 54 this year and don’t know why I’m still around. I haven’t got away with it, though. I’m insane. If I’m not, why am I taking so many psychiatric medications, antidepressants and seeing a therapist once a month? I’ve been in rehab 14 times, and still drink, but I try to keep it down to a glass of wine or a few beers." He became addicted to Viagra, which he calls "a great sleeping pill for the wife. By the time it worked she was snoring."

He pauses longer than usual, and adds bleakly, "I thought I’d work and put some money away so my wife can live well when she’s an old lady, because I’ll die first. That plan’s been wrecked, although I could drop dead this minute.

"You know what happened with Sharon? I’m a hypochondriac, so when the medical world has some new gizmo, I want to have a go. I heard about this body scanner which detects cancer, so I had it done, and at the same time they shoved a telescope up my butt and found a tiny polyp, which is how cancer starts, but it was benign. I told Sharon, ‘Maybe you should have it done.' So she went and they found a malignant tumour up her.

"It hit me like a freight train. I went on tour the following week, but can’t remember being on the road. You find yourself pissed off with God. I’m still in a state of ‘Is it really happening?'

"Chemotherapy knocks the crap out of her, but she’s going to recover. It might be a lot worse. I could be on the minimum wage with no health insurance. I can afford the best doctors. When you have cancer in the family, nothing else matters. It’s taught me that every day you lose is another page gone, so don’t sit there like a vegetable.

"I never realised TV is the most powerful form of entertainment on the planet. I still wonder what it all means. I was in Boston, where I’ve performed thousands of times, and this respectable middle-aged woman comes up to me and says, 'What the hell are you doing here?' I tell her I’m here to perform, and she goes, 'F***. You do that as well?' I’ve reached an audience with no idea I’m a rock ‘n’ roller. I’m pleased about that. I’m the working-class hero. Not bad for a guy from Aston.

"Of course, I’m ashamed of some things, but I believe life is planned before you’re born. I don’t take the TV series seriously. You wake in the morning and there’s a camera crew up your butt. It’s like having a fly in your eye that won’t go away. It plays havoc on the nervous system, you know, but so long as I’m making people laugh – at me, or with me – I don’t give a s***.

"I’m flavour of the month, the hottest ticket in town, but eventually we’ll be yesterday’s news. Then I’ll have serenity again. I hope."

Read more:

• Ozzy Osbourne's Black Sabbath bandmates lead tributes to star after death, aged 76
• Ozzy Osbourne and Black Sabbath play epic final show - and bring out fellow rock legends

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