Agatha Christie was a mystery writer.
Agatha Christie . On 15 September 2015 , coinciding with her 125th birthday , And Then There Were None was named the `` World 's Favourite Christie '' in a vote sponsored by the author 's estate . And Then There Were None is a mystery novel by English writer Agatha Christie , widely considered her masterpiece and described by her as the most difficult of her books to write . The Edgar Allan Poe Awards ( popularly called the Edgars ) , named after Edgar Allan Poe , are presented every year by the Mystery Writers of America , based in New York City .