Some crime writers seem to have a fictional afterlife of their own, shifting from plotters of crimes to solvers of them in works created by other hands.

In recent years Edgar Allan Poe has been a popular choice for this treatment, popping up in Andrew Taylor's American Boy and Louis Bayard's Pale Blue Eye while Arthur Conan Doyle, not above a spot of investigation in real life, is another perennial favourite, whether in the BBC's "Murder Rooms" series or "Twin Peaks" co-creator Mark Frost's "List of Seven".

Most bizarrely, dear old Agatha Christie is set to be paired with the BBC's favourite Time Lord in the next series of "Doctor Who". Now another writer from the Golden Age of British detection is being reinvented as a sleuth.

Inverness-born Elizabeth Mackintosh first found fame as the playwright Gordon Daviot, but it is as the crime writer Josephine Tey she is best remembered today and it is Josephine Tey who occupies centre stage in the debut novel of journalist Nicola Upson, An Expert in Murder.

Nicola has long considered placing Tey within the pages of a book, but revealed her original aim had been fact rather than fiction. "I suppose it must have been 15 years ago when I read The Franchise Affair,” Nicola said down the phone from her Cambridge home. "I was always very intrigued by that very, very thin biographical note that you got at the front of Penguin paperbacks. I tried to find out more about her and it just so happened that Virago, the publisher, had a competition for a new proposal for a new subject for a biography, so I did that and I got shortlisted. I did lots of fascinating stuff. I talked to Sir John Gielguid and lots of her colleagues who had worked with her around the time of her play 'Richard of Bordeaux', so I had a fairly comprehensive picture of her professional life, but her private life was still a bit of an unknown. It's become a bit clearer since then."

It was her partner who suggested Upson use the research in a novel and the kind of novel Tey herself is most associated with, the detective story. "What you've got in An Expert in Murder and the books that will follow it, is an entirely fictional detective puzzle, but hung on actual events in Tey's life and it will follow the pattern of her life as she grows older," Nicola added.

And it is "Josephine Tey" who is the heroine of Nicola's books, not Elizabeth Mackintosh. "I call her Josephine Tey because, though it follows the line of Elizabeth Mackintosh's life, the voice of the woman in these books is really the voice of the personality that we get in those eight crime novels: the seven she wrote as Tey and the one which was published as Gordon Daviot at first," Nicola continued. "That is really how people know her, so it seemed sensible to call her that."

She also conceded the use of the Tey name was a way of distancing the character of her books from the real author who inspired them because though they are based on real life, they are not designed as an accurate biography.

However, even Tey herself was wont to use her pseudonyms, including the male pen-name Gordon Daviot, in her every day life. "She was quite strict about that," Nicola commented. "Even close friends writing to her would use the name Gordon and when she constructed the Josephine Tey persona, she conducted all the Tey business as Tey. They were very different personas which people probably thought was a bit odd."

And for anyone putting their own fictional spin on the writer's life, these different personas and the secret aspects of Tey's life come almost tailor made. "You know, I could hug her!" Nicola declared. "It is a gift because it’s this business of gaps being more interesting than facts. The facts we have got are fascinating and I find it really absorbing she could carry out this double life, one in Scotland and one in London where she could become a completely different person.

"I imagine if someone had met her down at London when she stayed at a club they would have found it very hard to recognise her. She was very good at keeping the canvas blank."

If the books are successful, Nicola would love to follow Tey through her life up to her death in 1952. "How obliging of her to live through such fascinating years to write about because the social backdrop is wonderful," Nicola said. "It’s a very strong period and it’s interesting to see the circles that she moved in because that theatre set is fascinating. It’s like a parallel Bloomsbury which was going on at the same time, though they never met."

In contrast with her glamorous life with the theatre set in London was Tey's more restricted life at home in provincial Inverness. "She had to come home to look after her father on her mother's death, but it annoys me the way people portray that as such a sacrificial thing for her because boy did she make the most of it!" Nicola said. "Her Inverness life was not as duty bound or sad as people tend to portray it. She had a beautifully situated house and she carved out her own life in Inverness. There's a wonderful letter where she talks about how, very early on, she made a decision that she wasn't going to buy in to this endless round of coffees in the morning and teas in the afternoon. People thought she was very strange to do that. and at that time they didn't know she wrote, so she had no right to be strange. She didn't involve herself in the social life of Inverness. That wasn't just her, that was her whole family. If you talk to people in Inverness who knew them, they very much refer to them as a family who lived within themselves."

Tey’s decision to leave her money to the National Trust for England, rather than any Scottish charity’s may have also caused some bad feeling, Nicola suggested. "Because she wrote about England so well as well as Scotland it’s too often seen as: ‘Did she love England or did she love Scotland?’ Well, I think she loved both. If you read something like The Man in the Queue with that wonderful bit where she’s going back to Scotland by train, nobody could doubt how she felt about Scotland, she loved it."

Not as prolific as some of her contemporaries, Tey remains a hugely influential writer. A poll of British Crime Writers Association members for the 1990 Hatchards Crime Companion"saw her 1951 novel The Daughter of Time top the list of greatest crime novels (The Franchise Affair just missed out on a top 10 place, being voted in at number 11) and its central device of a bed bound detective solving a historical crime, in Tey's case the murder of the Princes in the Tower, has since been followed by others including Colin Dexter in The Wench Is Dead.

Tey has also provided material for film and television makers. Her early novel, A Shilling for Candles inspired Hitchcock's 1937 film Young and Innocent, her 1948 novel The Franchise Affair was filmed for the cinema in 1950 and television in 1988 and the 1980s also saw a television version of her romantic thriller of impersonation and false identity, Brat Farrar.

 Nicola acknowledged that Tey does not enjoy the public profile of her contemporaries like Agatha Christie or Dorothy, something she attributes in part to Tey's relatively early death in 1952. "She is, in that horrible phrase, a writer's writer. People as different as P. D. James and Val McDermid, even Raymond Chandler, have really rated her," Nicola said. "That popular thing hasn't happened but I hope that will change."

Nicola's books could play a big part in that. The publication An Expert in Murder has led to renewed interest in Tey and her works and in France the publication of Nicola's book has seen Tey's own books republished. "It's getting the people to read one, because she's not an acquired taste. And the people who love her really love her," Nicola said.

Nicola also regards Tey as a very modern writer. While the popular view of Tey is of someone warm and reassuring, the author took a very realistic view of the effects of crime rather than just a murder to provide an excuse for a puzzle.

"She did a lot to make it possible for us to write realistic fiction," Nicola said. "I don't think she gets the credit she deserves."

* "An Expert in Murder" by Nicola Upson, is published by Faber & Faber hardback £12.99 March 2008 (978 0 571 23770 8) and trade paperback £10.99 (978 0 571 23907 8).