Agatha Christie is the best-selling fiction author of all time
A collection of previously unheard recordings of crime writer Agatha Christie talking about her life and work has surfaced in Devon after lying undiscovered for 40 years.
The reels of tape, over 13 hours long, were discovered by the author's grandson in a cardboard box during a spring clean-out at Christie's former home in Torquay.
They date back to the 1960s and are working notes for her autobiography which was published posthumously in 1977.
But the recordings go into far greater detail about some aspects of Christie's life than the finished book, with descriptions of what life was like in wartime Britain, her honeymoon with her second husband and the reason why she would never let her legendary sleuths Hercule Poirot and Miss Marple meet.
Hercule Poirot, a complete egoist, would not like being taught his business or having suggestions made to him by an elderly spinster lady
Christie also provides some insight about how she came to create Miss Marple, the elderly spinster who acts as an amateur detective and appears in 12 of her novels.
"Miss Marple insinuated herself so quietly into my life, that I think I hardly noticed her arrival. I just had the idea, possibly for a series of six short stories for one special magazine, and I chose the people who I thought would be suitable.
"An old spinster lady living in a village, the sort of old lady who would have been rather like some of my grandmother's cronies... old ladies like I had seen in the private hotel in South Kensington... and old ladies like I had met in so many villages where I had gone to stay as a girl."
When it comes to solving mysteries Miss Marple is shrewdly intelligent
She is adamant that Miss Marple is not based on her grandmother but admits there are similarities.
"She had this in common with my grandmother, that although a completely cheerful person she always expected the worst of anyone and everything - and with almost frightening accuracy usually proved right."
The tapes, recorded on a Grundig Memorette reel-to-reel tape recorder, are believed to have been made at Christie's home, and in some sections her dogs can be heard barking in the background.
Again and again, she hits the pause button as she takes a moment to think. Her relaxed, informal tone is charming to listen to and a rarity, as she disliked being interviewed, was shy and wary of media attention.
Only a handful of recordings of her voice are known to exist - including a 1955 interview for the BBC and a 1974 recording for the Imperial War Museum Sound Archive in which she recounts her experiences in a World War I dispensary which gave her a working knowledge of poisons - something which would feed into her murder mysteries.
Unfortunately, the tapes give no insight into one of the most intriguing parts of her life - the mysterious episode in 1926 when, having been told by her first husband Archie that he wanted a divorce, Christie drove off alone from their Sunningdale home, abandoned her car, then took a train to Harrogate in Yorkshire where she registered herself at the Hydro Hotel as Mrs Neele (the name of her husband's mistress).
She spent 12 days in Harrogate, shopping, lunching in tea rooms, having beauty treatments and even singing with the hotel's dance band, whilst becoming the subject of a nationwide search by the tabloid media.
It's also wonderful to hear that latent humour and the assurance in her voice, as she talks about these ridiculously familiar characters
Laura Thompson, Agatha Christie's biographer
Her family now assume that she had a nervous breakdown, and after she was found she was diagnosed by doctors as suffering from amnesia. The media frenzy over her disappearance is thought to be one of the reasons why she tended to avoid interviews and became increasingly reclusive.
Matthew Prichard, Agatha Christie's grandson, says the tapes bring an overwhelming sense of of his grandmother.
"She has little mannerisms, like the minor cough in the middle of sentences, which I had forgotten about - and all this comes back to you," he says.
He points out that his grandmother was shy - and would never have recorded her thoughts if there had been anyone else present.
Laura Thompson, Agatha Christie's biographer, recalls her as "a profoundly mysterious person".
She describes it as a jolt, hearing Christie's voice 32 years after her death.
"It was so nice to hear again, the essence of Agatha. She really belongs to an England that no longer exists - and you can hear that in the tapes. It's also wonderful to hear that latent humour and the assurance in her voice, as she talks about these ridiculously familiar characters."
Overwhelmingly, there is a sense from the recordings of a feisty and determined personality.
"People never stop writing to me nowadays to suggest that Miss Marple and Hercule Poirot should meet. But why should they meet? I'm sure they would not like meeting at all," she says.
"Hercule Poirot, a complete egoist, would not like being taught his business or having suggestions made to him by an elderly spinster lady. Hercule Poirot - a professional sleuth - would not be at home at all in Miss Marple's world."
Crime writer Agatha Christie at an unknown event in July 1967
"They are both stars and stars in their own right. I shall not let them meet, unless I feel a very sudden and unexpected urge to do so."
And speaking about The Mousetrap - famed as the longest running play in London's West End since its first performance in 1952 - she said she thought its success was "90% luck" and that "there was a bit of something in it for almost everybody". She recollects that she predicted it would not run for more than eight months.
And she admits she initially had some doubts about it.
"I must say that I had no feeling whatsoever that I had a great success on my hands... I went with some friends and I thought, 'I've let it have too many humorous situations, there's been too much laughter, it's taken away from the thrill'.