I RAN INTO MY FORMER tutor at a memorial service in Oxford last week. Thirty years on, she asked me if I was disappointed that I hadn’t got a first.

Once I had recovered from my astonishment at the extent of her memory, I said that even if I did have a first-class mind, I have only second- class application.

That’s why I became a journalist and a writer of fiction rather than an academic. I get bored quickly and I have always been good at making three facts go a long way. Until I started work on my latest novel, The Grave Tattoo, I hadn’t done much rigorous research since I graduated.

The moment that the idea for this book surfaced, I felt daunted by the amount of background digging I knew it was going to take. That’s probably no small part of the reason that it took about eight years from the initial sparking of the idea to the point where I was ready to write.

The roots of the book lie in a single fact and a single rumour. The fact: William Wordsworth and Fletcher Christian were schoolmates. The rumour: Christian didn’t die on Pitcairn; he escaped and made his way home to the Lake District.

Armed with these and nothing more, I decided that if he had come home, Christian would have wanted to put his side of the story. And who better to put it to than his old schoolmate and family friend, William Wordsworth, now a respected poet? Wordsworth would have felt compelled to make poetry of it. But it would be poetry that he could never publish because to have done so would have been tantamount to admitting to harbouring a fugitive.

It was a compelling notion, but to see whether it would fly, I had to find out a lot more about both men. My sole knowledge of Christian was based on the Trevor Howard/Marlon Brando film Mutiny on the Bounty.

And although I had studied Wordsworth as an undergraduate, our method had been to consider the life only when it impinged directly on the art. So I knew the version of himself that Wordsworth had presented through The Prelude but I couldn’t remember if I knew how accurate that was.

There was no escape. I was going to have to sit down and do some proper reading. Biographies. Diaries. Letters. Normally, I prefer the sort of research that involves tracking down a living being who possesses the expertise I need to plunder, then plying them with food and drink till I have all I need to know. That’s more or less how I came by the forensic details in the book, and it’s a lot more fun than ploughing through biographies of long-dead poets, no matter how well written.

There are a lot of biographies of Wordsworth. Most are hefty tomes of excellent scholarly research, loaded with fact and sturdy with conclusions that seem to make sense. Juliet Barker and Stephen Gill seem to me the finest proponents of this reliable and intelligent approach.

But I did stumble across a couple of books whose theories seemed so outlandish that I felt reassured about the apparent craziness of my own idea. My favourite was the one in which Wordsworth and his cronies were painted as the Burgess, Philby and Maclean of their day.

There were some surprises too — discovering, for example, that it was Wordsworth who suggested to Coleridge that he use the until-then blameless albatross as a metaphor for sin and guilt. And that it was made at around the time when he could easily have learnt from Fletcher’s brother Edward, the Wordsworth family lawyer, that the Bounty crewmen had shot and eaten albatross on their voyage.

Then there was Wordsworth’s French girlfriend and their illegitimate child — a small detail that he overlooked in his autobiographical verse and a secret the family kept hidden until a couple of academic detectives unearthed it in the 1920s.

If the voluble Wordsworths could all keep one momentous secret, I reasoned, they could surely keep another.

When it comes to Fletcher Christian and the aftermath of the Bounty mutiny there is little of an authoritative nature. The accounts we have were all given long after the events and they bristle with as many inconsistencies and improbabilities as there are wild theories to stitch them together.

We do know that there is no grave on Pitcairn for Christian, the man who led the mutiny and founded the colony there. Lesser figures have memorials, but not him. We also know that reports of his return to the land of his birth came from sources as diverse as a fellow officer on the Bounty and the poet Robert Southey.

In everything I read, I found nothing to contradict my beautiful, crazy idea.

There came a point where I had to test it out. That was when I was able to return to my normal method. Robert Woof, the director of the Wordsworth Trust, the curator of Dove Cottage and the Wordsworth Museum, and walking encyclopaedia on all things Wordsworthian, agreed to meet me.

Hesitantly at first, then with more confidence, I outlined my idea and my research. He listened patiently, corrected me on a couple of details, then announced that he found the idea, though improbable, charmingly plausible. I felt as if a huge weight had been lifted from my shoulders. My only regret is that he died before the book was published.

I read far too many words in pursuit of this book. I fell into the trap, for a time, of allowing the research to become more important than the story.

But I do have second-class application and I am happy to reveal that I have now forgotten almost all of it. All that remain are the three facts I need for bluffing.

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