The attraction now, to romantic souls, is twofold. First, the 37 inhabitants are reputed to be direct descendants of those colourful vagabonds; second, their society is said to be a trouble-free slice of paradise.

Dea Birkett, a British journalist, certainly thought so, largely on the strength of watching Mel Gibson's film version of the famous mutiny, The Bounty. That's enough to warn you that her judgment is a little suspect, although, to be fair, it only took simple research for her to find that the first claim is an exaggeration. Most of the mutineers died within a few years of arrival, either by accident or more often by someone else's design - usually a disgruntled Polynesian. Some of their family names live on, but today's population is equally the result of later arrivals.

A trip to the island was necessary to disprove the second. Not many of Pitcairn's fan club get that far: you need permission to land and a good reason to go.

But Birkett is a determined and resourceful woman, as becomes clear as Serpent in Paradise gets under way. She persuaded Britain's post office to sponsor her on the pretence of studying Pitcairn's mail system - not as crazy an idea as it sounds.

No letter has ever been sent along the 6.5 kilometres of island road. Why should they bother? Today's eight families live next door to each other in Pitcairn's only settlement and they are all on the phone. But stamps are one of the island's main sources of income - a Pitcairn postmark is a must for many collectors - and Birkett soon found herself on board a cargo ship that would pass by this most remote of destinations where, with luck, she could be dropped into one of the islanders' long boats.

The result of all this, and her lengthy stay on Pitcairn, is a book that says virtually nothing about the post - perhaps she had to apologise to the Royal Mail on her return - but a great deal about the island, its history and most of all the interaction of its inhabitants with each other and with outsiders.

Serpent in Paradise is not a comfortable travelogue; Birkett's stay wasn't an easy one and her disillusionment with her hosts and, more importantly, her original, simplistic view of how such an incestuous community would function, make that impossible.

It is instead strangely compelling, tinged with foreboding and packed with the descriptive language of a keen observer. It is unusual to find a travel book that you can't put down - even a travel book which, frustratingly, contains no pictures - but, thanks to the pace of a novelist and Birkett's sometimes painful honesty, you simply have to keep going until you find out exactly in what way her dream was finally shattered.

This, it must be said, was not the fault of the islanders, although Birkett doesn't always see it that way. They have a way of life honed over generations that revolves around survival - Birkett's hostess keeps freezers and fridges packed with 'essentials' that never get used, simply because isolation breeds that kind of caution.

They have a keen sense of their own history, which no outsider can really share, a language largely their own, their lives are tough and the 37 of them know each other too well. Their horizons too are limited, literally to the horizon. There is nowhere to go on Pitcairn except to the shore or back home.

It takes time for Birkett to learn this and by then it is too late. Acceptance, however polite the islanders might be, is impossible. Outsiders, except perhaps the Seventh Day adventist pastor who keeps them on the straight and narrow and largely off alcohol, should not outstay their welcome.

A quick, and rather foolish, fling with a Pitcairner whose wife is away in New Zealand seals her fate.

The assignation, supposedly a secret early-morning affair, becomes common knowledge within days and Birkett decides it is time, quietly, to leave.

Back in Britain, she has stripped the veneer off this little community through her accomplished prose.

It is done largely with sympathy, but stripped it she has, giving an airing to the island's squabbles and its petty habits that makes Serpent in Paradise both fascinating for the outsider and, I am sure, wholly unwelcome on Pitcairn, especially to the family of her one-off lover.

And there lies the one objection to Birkett's work. At no time did she explain her purpose to the Pitcairners; she shared their lives for many months with a kind of closeness - pleasant or otherwise - that only such a community can offer.

In fact, her book shows how clearly she knew earlier writing had caused deep offence: ' 'Do you enjoy reading?' I asked Nola, who was concentrating on her thatch. 'No,' she said. 'Nawa read. All ha books full of shit. People write bad things about Pitcairn in books . . . Them people who go write books on Pitcairn should go wipe.' When Nola said 'go wipe' it was with the force of a bullet and as frightening as having a gun to your head.' Point taken, Nola, however enjoyable this particular Pitcairn book might be.

Serpent in Paradise by Dea Birkett Picador, $118