It was a mystery worthy of the great writer herself.
At shortly after 9.30pm on Friday 3 December, 1926, Agatha Christie climbed the stairs of her Berkshire home and kissed her sleeping daughter Rosalind, aged seven.
She then made her way back downstairs, climbed onto her Morris Cowley and drove off into the night.
|Young Agatha: Getty Images|
She would not be seen again for another 11 days.
Her disappearance would spark one of the largest manhunts ever mounted. More than one thousand policemen were assigned to the case, along with hundred of civilians. For the first time, aeroplanes were also involved in the search.
The Home Secretary, William Joyson-Hicks urged the police and nation to make faster progress in finding the Christie.
Two of Britain’s most famous crime writers, Sir Arthur Conan Doyle, creator of Sherlock Holmes, and Dorothy L Sayers, author of the Lord Peter Wimsey series, were also drawn into the search; it was hoped their specialist knowledge would help find the missing writer.
It did not take long for the police to find Agatha Christie’s car. It was found abandoned on a steep slope at Newland’s Corner near Guilford. But there was no sign of Christie herself and nor was there any evidence she’d been injured in the accident.
|The car. But where's the driver?|
As the first day of investigations progressed into the second and third - and there was still no sign of her - speculation began to mount. The press had a field day, inventing ever more colourful theories as to what had happened.
It was the perfect story, with all the elements of an Agatha Christie whodunit. Close to the accident scene was a natural spring known as The Silent Pool. It was reputed to be the site of the death of two young children and some journalists were convinced that the novelist had drowned herself.
Yet suicide seemed unlikely, for her professional life had never been better. Her sixth novel, The Murder of Roger Ackroyd, was selling well and she was already a celebrated household name.
|With Archie the unfaithful|
Some said the incident was nothing more than a publicity stunt - a clever way to promote her new book.
Others hinted at a far more sinister turn of events. There were rumors that she’d been murdered by her husband, Archie Christie, a former First World War pilot - and philanderer - who’d been unfaithful to his wife and was known to have a mistress.
Arthur Conan Doyle, a keen occultist, tried using paranormal powers to solve the mystery: he took one of Christie’s gloves to a celebrated medium in the hope that it would provide answers. It did not.
Dorothy Sayers also wanted to crack the mystery. She visited the scene of the writer’s disappearance in the hope it would provide clues. This provide no less futile.
By the eleventh day of the search, the news had spread around the world. It even made it onto the front page of the New York Times.
Not until 14 December was Agatha Christie finally found safe and well in a hotel in Harrogate - but in circumstances so strange that they raised more questions than they solved.
|Headline news around the world|
She herself was unable to provide any clues as to what had happened: she remembered nothing. It was left to police to piece together what might have taken place.
It seems that Christie had traveled from her home to London - crashing her car en route - and then boarded a train to Harrogate.
On arriving at the spa town, she checked into the Swan Hydro - now the Old Swan Hotel - with almost no luggage; bizarrely, she used the assumed name of Theresa Neele, her husband's mistress.
|Found: in the Swan Hydro|
Harrogate was the height of elegance in the 1920’s and filled with fashionable young things. Agatha Christie did nothing to arouse suspicions as she joined in with the balls, dances and palm court entertainment.
She was eventually recognized by one of the hotel’s banjo players, Bob Tappin, who alerted the police. They tipped off her husband, Colonel Christie, who came to collect Agatha immediately. She was in no hurry to leave. Indeed, she kept him waiting in the hotel lounge whilst she finished dressing for dinner.
Agatha Christie never spoke about the missing 11 days of her life and over the years there has been much speculation about what really happened between 3rd and 14th December 1926.
|Miss Marple: could she have solved it?|
Her husband had his own theory: he said she'd suffered a total memory loss, probably as a result of the car crash.
But according to biographer Andrew Norman, the novelist may well have been in what’s known as a ‘fugue’ state, or, more technically, a psychogenic trance. It’s a rare condition brought on by trauma or depression.
Norman says that her adoption of a new personality - Teresa Neele - and her failure to recognize herself in newspaper photographs were signs that the novelist had fallen into psychogenic amnesia.
'I believe she was suicidal,' said Norman. 'Her state of mind was very low and she writes about it later through the character of Celia in her autobiographical novel, Unfinished Portrait.’
Christie soon made a full recovery and once again picked up her writer’s pen. She was no longer prepared to tolerate her husband’s philandering: she divorced him in 1928 and later married the distinguished archaeologist, Sir Max Mallowan.
We’ll probably never know what really happened in those lost 11 days. Agatha Christie left a mystery that even Hercule Poirot or Miss Marple would have had difficulty in solving.
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