Pity the poor celebrity.

They fight and struggle from childhood to fulfil their destiny, to become famous.

And then what do they find? The streets become a prison. They can't step outside their front door without finding themselves in the next day's papers.

The ever-watchful eyes of the paparazzi

And if the paparazzi don't get them, the stalkers will.

What's a celeb to do? Invite the photographers from Hello! magazine in, to give them a tour round their charming new home, perhaps. Or consider becoming a recluse.

Not even that works, though. The very rarity of their public appearances increases the bounty on their heads. Snatched photographs become even more valuable and palatable to hungry news editors.

Recluses can scarcely expect the press to be deferential towards them.

Stanley Kubrick, photographed in 1975, on the set of Barry Lyndon

Richard Ingrams, former editor of Private Eye, wrote last week about the late Stanley Kubrick: "If you want people to think you are a genius, the best thing you can do is to shut yourself away. . .The more reclusive he became the greater his reputation grew, until he earned the supreme accolade of being described as 'legendary'. This is a word which is never bestowed on artists who speak to journalists or who can be seen enjoying a drink at the local."

J D Salinger is one who may see the irony of being one of the world's most famous recluses. But it's unlikely we shall ever know what he thinks - he never speaks to reporters, it is 34 years since he last published anything, and his friends have been fiercely loyal to his privacy.

Local curiosity

Eighty this year, he lives in a small town, Cornish, in New Hampshire, where the townsfolk are accustomed to seeing him around. Fond of him as a local curiosity, they respect his privacy and most will politely refuse to tell reporters where he lives.

So why shouldn't he be allowed to live his life in peace?

Sarah Aspinall , producer and director of a profile of Salinger for BBC Two's Close Up, said she did have worries about invading his privacy. However, she and the executive producers had decided they could make the film without going down the road of invasion.

"We wanted to look at the book, the fandom, and the sect of reclusiveness," she said.

Greta Garbo as Mata Hari

"In the world of the arts there are few investigative subjects to get our teeth into. It's always tempting for journalists to take up something that's a challenge, but to the public it's the Greta Garbo syndrome. We can project any of our fantasies on to that person.

"We always imagine there's an interesting dark secret that we have the right to. But often the truth is more boring, and they just can't stand the whole public thing.

"Bearing in mind the media excesses, it's hardly surprising if someone chooses to withdraw from public life. In fact it's surprising more people don't do it and that people actually want to take part in the media circus."

Genuine public interest

One of Salinger's lines, explaining his desire for privacy, is "It's all in the book", she said.

But for her that is not enough. "Of course nobody buys that, that's not all there is to know."

If the film's producers needed to justify their interest in Salinger, they could easily illustrate a legitimate public interest - simply the impact Salinger's 1951 novel Catcher in the Rye has had on the world.

In its main character, Holden Caulfield, Salinger created one of the defining points of teenage angst and rebellion. It helped shaped each generation that came after it.

John Lennon, shot by Mark Chapman. His producer, Phil Spector, is also reclusive

The book's influence has also been felt on a more specific level - witness Mark Chapman's notoriously dispassionate statement: "The reason I killed John Lennon was to promote the reading of J D Salinger's Catcher in the Rye."

The man who attempted to assassinate Ronald Reagan in 1981 also had a copy of the book in his belongings.

World famous recluse

The point is made by one of Salinger's friends, who told Close Up: "Nobody asked Jerry to write all those books. Nobody asked him to write Catcher in the Rye, to become world famous."

He may well ask himself why all these people will not leave him alone, and at least part of that reason must be because of the connection people feel with Holden Caulfield.

His unpredictable and capricious dislikes of people, things or even words, strikes powerful memories of teenage-hood.

How then, many people wonder, can an author who has made such a powerful connection with such a large audience over decades have no interest in communing with the outside world?

Another of his friends tells the programme, interest in recluses is a natural reaction. "Greta Garbo was right. 'I want to be alone.' I mean, just cut yourself off," he says. "The more you are mysterious, the less people know about you, the more they want to know. That's the nature of human inquiry."

Smell of blood

And yet. . .once someone has published something does that mean they are public property for the rest of their lives? It's nearly half a century years since Catcher in the Rye was published and 34 years since Salinger's last book.

Nick Broomfield, on the trail of Margaret Thatcher (picture: Channel 4)

As other documentary makers have shown, the chase can be better than the kill. Trying to track down an elusive subject, persuading old friends to talk, even finding someone who once met the target, simply increases the appetite. It was Nick Broomfield, after all, who interviewed a woman who had converted a toilet discarded by Margaret Thatcher into a plant pot.

Having convinced many people with more or less tangential links with Salinger to talk, Aspinall hit gold with one of his former girlfriends, Joyce Maynard. She was someone who had, Roy Ackerman said, "penetrated literature's last Fort Knox".

And indeed there are fascinating revelations about his prolific letter-writing - particularly to young women. And about the number of books he has finished, but keeps locked in a huge safe in his house.

Sarah Aspinall said a veil was drawn over some of what they found. "We could have shown much more, there was more material and there were more conclusions that we could have drawn. For instance, there is footage of him walking with his current wife. I felt that it was quite personal, and it felt like an invasion of her privacy," she said.

But crucially there was at last someone who knew what the life of the recluse was like. Perhaps inevitably, it sounds rather dull.

He eats peas for breakfast, has a walk, does some yoga, writes some letters.

Nevertheless, he - like Kubrick and nearly every other celebrity recluse - cannot stop people being interested, however hard he tries.

"I think the public has a right to know," said Aspinall. "He is a professional author, he has made a great deal of money, and in doing that, he must recognise that giving some biographical information is part of the package that happens when you publish.

"He wanted the book to be an international bestseller, and I don't think he can opt out of that now. We have a right to satisfy our curiosity."