Dame Agatha Mary Clarissa Christie, Lady Mallowan, DBE (née Miller) was an English writer known for her 66 detective novels and 14 short story collections, revolving around fictional detectives Hercule Poirot and Miss Marple. She also penned the world's longest-running play, The Mousetrap, which has been performed in the West End of London since 1952. A luminary during the "Golden Age of Detective Fiction," Christie has been celebrated as the "Queen of Crime" and the "Queen of Mystery," with her estate now trademarking these monikers. Furthermore, she authored six novels under the pseudonym Mary Westmacott. In recognition of her literary contributions, she was appointed a Dame (DBE) by Queen Elizabeth II in 1971.

Christie's journey into literature began in the affluent upper-middle-class family settings of Torquay, Devon, where she was largely homeschooled. Despite initial rejections, her career took a pivotal turn in 1920 with the publication of The Mysterious Affair at Styles, introducing the beloved detective Hercule Poirot. Her personal life saw its share of drama, notably her mysterious disappearance in 1926 following the breakdown of her marriage to Archibald Christie and the death of her mother, a saga that captured international headlines. Christie's work during both World Wars in hospital dispensaries deepened her knowledge of poisons, a detail that intriguingly featured in many of her stories.

Her marriage to archaeologist Max Mallowan in 1930 enriched her life and works, as she spent months each year on digs in the Middle East, infusing her narratives with first-hand archaeological insights. According to UNESCO's Index Translationum, Christie is the most-translated individual author, with her novel And Then There Were None ranking among the top-selling books of all time, boasting approximately 100 million copies sold.

Christie's accolades include the first recipient of the Mystery Writers of America's Grand Master Award in 1955, and her play Witness for the Prosecution received an Edgar Award for best play later that same year. In a testament to her enduring legacy, The Murder of Roger Ackroyd was voted the best crime novel ever by professional novelists of the Crime Writers' Association in 2013, and And Then There Were None was named the "World's Favourite Christie" in 2015 in a vote sponsored by her estate. Her works have been extensively adapted for television, radio, video games, graphic novels, and over 30 feature films, affirming her as a seminal figure in the mystery and detective genre.