Dame Agatha Mary Clarissa Christie, Lady Mallowan, (née Miller; 15 September 1890 – 12 January 1976) was an English writer known for her sixty-six detective novels and fourteen short story collections, particularly those revolving around fictional detectives Hercule Poirot and Miss Marple. She also wrote the world's longest-running play The Mousetrap, performed in the West End from 1952 to 2020, as well as six novels under the pseudonym Mary Westmacott. In 1971, she was appointed a Dame Commander of the Order of the British Empire (DBE) for her contribution to literature.
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If I had kept all these things neatly sorted and filed and labelled, it would save me a lot of trouble. However, it is a pleasure sometimes, when looking vaguely through a pile of old note-books to find something scribbled down, as: Possible plot—do it yourself—girl and not really sister—August— with a kind of sketch of a plot. What it's all about I can't remember now; but it often stimulates me, if not to write that identical plot, at least to write something else.