As Jane Marple sat basking in the Caribbean sunshine she felt mildly discontented with life. True, the warmth eased her rheumatism, but here in paradise nothing ever happened.

Eventually, her interest was aroused by an old soldier's yarn about a strange coincidence. Infuriatingly, just as he was about to show her an astonishing photograph, the Major's attention wandered. He never did finished the story…

Agatha Christie was born in Torquay in 1890 and became, quite simply, the best-selling novelist in history. Her first novel, The Mysterious Affair at Styles, written towards the end of the First World War, introduced us to Hercule Poirot, who was to become the most popular detective in crime fiction since Sherlock Holmes. She is known throughout the world as the Queen of Crime. Her books have sold over a billion copies in the English language and another billion in over 100 foreign languages. She is the author of 80 crime novels and short story collections, 19 plays, and six novels under the name of Mary Westmacott.