Best-selling author - The world's favorite female crime writer is Agatha Christie (1890-1976), whose 78 novels have sold over 2 billion copies worldwide. Her most famous sleuths, Miss Marple and Hercule Poirot, are portrayed here my Margaret Rutherford (1892-1972) in the 1964 MGM film of Murder Ahoy and Peter Ustinov in the 1978 version of Death on the Nile, which also featured David Niven (1909-83) and Bette Davis (1908-1989). (Photo: Kobal Collection/Syndication International)