High above Sunset Boulevard in the Holmby Hills where Elvis Presley and Frank Sinatra once lived, Playboy Mansion stands in all its gothic glory.

Set in six acres, boasting a pool, a grotto, an aviary and a zoo (complete with monkeys, flamingos and - of course - rabbits), the mansion is a star in its own right, having appeared in Beverly Hills Cop II and Sex And The City.

The owner of the mansion, and the founder of the Playboy empire, Hugh Hefner is half an hour late for our interview.

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Playmates: Hugh Hefner with Bridget Marquardt, Holly Madison and Kendra Wilkinson

I've been told he's at the doctor's - and I'm worried. After all, he's almost 81 years old and a former stroke victim.

Far worse, he still lives a Viagra-fuelled lifestyle in which he regularly has sexual relations with his three girlfriends, each one of them half a century his junior.

Moreover, rumour has it that he is on the verge of making one of them - Holly Madison, 27, a former Miss Hawaiian Tropic whose burning ambition is to visit every Disneyland on the planet - his third wife.

All deeply stressful for the universe's Number One Playboy and the perfect recipe for a heart attack.

So as I sit in Hefner's ersatz Elizabethan oak-panelled library - I am watched over by a vast photograph of a Playboy centrefold whose bust seems to have been manufactured in one country, then stuck on her body in another, plus a faux Holbein which quaintly immortalises 'Hef' as Henry VIII - I am convinced that any moment Hefner will ascend to that Bunny club in the sky.

Just as I am consoling myself with the thought that he has had a full innings - starting out as a Chicago copywriter, founding Playboy magazine with Marilyn Monroe as his first centrefold, and ultimately selling seven million copies of the magazine a month and opening 23 Playboy clubs (and making love to 1,000 women along the way) - the door bursts open and there he is, alive and looking surprisingly healthy.

At around 5ft 10in, dressed in blue jeans, wearing a red and navy checked shirt, loafers, his hair grey and his face lined and unlifted, Hefner could just as easily be mistaken for a teacher, like his parents, both Methodists from the Mid-West.

"My parents were church-going people, but I think in a certain sense they lived half-lives," he says, presumably referring to their modest incomes and religious boundaries. It is an accusation that can hardly be levelled at him. He nods sagely: "I think I am living such a full life because I grew up observing their halflives."

His mother, though, was prescient enough to invest $1,000 in the first Playboy magazine. "She did it not because she believed in the concept, but because she believed in her son," he says.

That said, he also admits that his mother was very repressed.

"There was no hugging and kissing in my family," he says. Just as I am about to venture "Well, you've certainly made up for that", he says: "I think to some extent my life has been an over-reaction to that."

That's really the thing about Hugh Hefner. Try to analyse him and he's already one step ahead, every bit the psychology student he once was.

While anyone who hasn't met him might be tempted to sneer, to lambast him as a sultan of sleaze, his shrewdness should not be underestimated.

An adman to the very bone, Hefner tapped into the American psyche, with its puritanical roots and deep-seated desire to deny the dark side of sex. That first centrefold of Monroe, back in 1953, presented her as the girl next door in all her innocent glory.

While his competitors, including seedy Penthouse boss Bob Guccione, degenerated into publishing photographs of women in poses seen only by their gynaecologists, Hefner refused to follow suit.

In many ways, while shamelessly trading in sex, his magazine was oddly staid, mixing nude photographs with supposedly highbrow interviews and features.

Brazen hypocrisy, or the unlikely legacy of those Methodist origins? Hefner would insist it was the latter, although the evidence from his private life is decidedly equivocal.

His first sexual experience was with his first wife, Milly, whom he met while they were both in college.

"I think the relationship was probably held together by two years of foreplay. That wasn't unusual for our time. In fact, most of my immediate friends didn't have sex until they married. Milly and I had it just before," he says.

"I had literally saved myself for my wife, but after we had sex she told me that she'd had an affair. That was the most devastating moment in my life. My wife was more sexually experienced than I was. After that, I always felt in a sense that the other guy was in bed with us, too."

Nonetheless, he and Milly remained married for ten years and had two children, Christie, now 55, and David, 52. Since the mid-Eighties, Christie has been chairman and chief executive officer of

Playboy, while Hef has remained the magazine's editor-in-chief.

Divorced from Milly at the height of the swinging Sixties, Hefner became a swinger par excellence, hosting a TV show, Playboy's Penthouse, and dating a series of Playboy centrefolds, including Britain's Marilyn Cole.

"The stereotypical assumption is that English women are repressed, but I don't think that's true any more. Once you get past that repression, they are very wild," he says, with something of a nostalgic gleam in his eyes.

Some of the world's most famous women - from Joan Collins to the late Anna Nicole Smith - have bared their bodies in the pages of Playboy, while philosopher Jean Paul Sartre, artist Salvador Dali, authors Vladimir Nabokov, Ian Fleming, Truman Capote and Cuban dictator Fidel Castro (among others) have bared their souls in Playboy interviews.

U.S. President Jimmy Carter famously confessed in the magazine that he had "committed adultery in my heart many times".

Hefner seemed to share no such inhibitions, maintaining a veritable harem of pliant female companions. However, in 1989, after he married former Playmate of the Year Kimberley Conrad, he disbanded his harem and - temporarily at least - broke his pattern.

"We were together eight-and-a-half years and I was faithful all that time," he says, ruefully, rather than proudly.

"Fidelity wasn't a problem for me. I was ready. Quite frankly, I got married after I had a stroke and I think I was escaping into what I perceived as a safe harbour. And I really felt that marriage was going to be the epilogue to my life.

"I wasn't tempted by other women. I felt older then than I do now," he says, then adds: "But I think that men are less capable of monogamy than women. I think that's built in because the female of the species is generally made for nesting and for raising the next generation."

He and Kimberley had two sons, Marston, now 16, and Cooper, 15, but then separated. At around that time, Viagra was unleashed upon the world, and Hefner became its foremost advocate.

"It was very helpful," he says with a puckish grin.

Consequently, at one point, he was simultaneously dating what he describes as "between seven and ten women".

Only now, almost ten years since splitting from Kimberley and moving a series of women into the mansion, he appears to have found his last love.

Holly Madison, 27, grew up in Alaska, then Oregon, and went on to study psychology and theatre at Loyola Marymount University in Los Angeles, moonlighting as a roller-skating waitress and a Hawaiian Tropic model.

Given her blonde good looks, one party invitation led to another, and soon she - and fellow Playmates Kendra Wilkinson, 23, and Bridget Marquardt, 32 - were living at the mansion, all three of them as Hefner's girlfriends.

Right now, Holly is the woman whose company Hef appears to enjoy the most. "I love her more than either of the two women I married," he says, adamantly.

"She completes me. Everything I do is more enjoyable because I share it with her. We have common interests in movies and in music and we are very compatible sexually.

"Am I going to marry Holly? I don't think so. But I do think that eventually Holly and I will have a monogamous relationship. Do Kendra and Bridget know that? Sure, it's fine with them. They are here for different reasons."

Different reasons? "I'm a realist," is his reply. Then he goes back to the subject of Holly. "She's as close as I've found in my life to a soulmate," he says.

Then why not marry her? "I've seen what marriage does to a soulmate," he says, firmly. "People stop trying."

But what about the age difference between him and Holly?

"I am still the boy who dreamed the dreams," he says, "That's who I am."

"Peter Pan?" I offer, helpfully. "In a certain sense,' he says, 'But this is not Michael Jackson's Neverland."

Then he tells me that he intends to be buried next to Marilyn Monroe. "Although I didn't know her, I bought the plot next to hers. It seemed romantic."

Right now, though, Viagra, stress and age aside, Hugh Hefner has no intention of joining Marilyn Monroe in the after-life.

"This is the best time of my life," he says. "Who in this world, on this planet, has a better life than I do? Nobody. If I had a chance to live again, I would hope I would be me again. In other words, it doesn't get better than this. I still have a sense of wonder at how far I've come, and I'm not going to lose that. I think I'm the luckiest guy on the planet."

Others may beg to differ. What is not in dispute is how much Hefner has achieved. But the manner in which he has made his fortune - and conducts his private life - will leave many with a sense of unease.