79: 1920 The Mysterious Affair at Styles (her first book, which introduced Hercule Poirot) 1922 The Secret Adversary (introduced Tommy and Tuppence) 1923 Murder on the Links 1924 The Man in the Brown Suit 1925 The Secret of Chimneys 1926 The Murder of Roger Ackroyd 1927 The Big Four 1928 The Mystery of the Blue Train 1929 The Seven Dials Mystery 1930 The Murder at the Vicarage (introduced Jane Marple) 1930 The Mysterious Mr Quin (introduced Mr Harley Quin) 1931 The Sittaford Mystery 1932 Peril at End House 1933 The Hound of Baskerville (twelve short mysteries) 1933 Lord Edgware Dies 1934 Murder on the Orient Express 1934 Parker Pyne investigates (twelve short mysteries) 1934 The Listerdale mystery (twelve short mysteries) 1935 Three Act Tragedy 1935 Why didn't they ask Evans? 1935 Death in the Clouds 1936 The A.B.C. Murders 1936 Murder in Mesopotamia 1936 Cards on the Table 1937 Death on the Nile 1937 Dumb Witness 1938 Appointment with Death 1939 Ten Little Niggers (also known as And Then There Were None, Ten Little Indians) 1939 Murder is Easy 1939 Hercule Poirot's Christmas 1941 Evil under the Sun 1941 N or M? 1941 One, Two, Buckle My Shoe 1942 The Body in the Library 1942 Five Little Pigs 1942 The Moving Finger 1944 Towards Zero 1944 Sparkling Cyanide 1945 Death comes as the End 1946 The Hollow 1947 The Labours of Hercules (twelve short mysteries featuring Hercule Poirot) 1948 There is a Tide (also known as Taken at the Flood) 1949 Crooked House 1950 A Murder is Announced 1951 They Came to Baghdad 1952 Mrs McGinty's Dead 1953 A Pocketful of Rye 1953 After the Funeral 1955 Hickory Dickory Dock 1955 Destination Unknown 1956 Dead Man's Folly 1957 4.50 from Paddington 1957 Ordeal by Innocence 1959 Cat Among the Pigeons 1961 The Pale Horse (murder by thallium) 1962 The Mirror Crack'd from Side to Side 1963 The Clocks 1964 A Caribbean Mystery 1965 At Bertram's Hotel 1966 Third Girl 1967 Endless Night 1968 By the Pricking of my Thumbs 1969 Hallowe'en Party 1970 Passenger to Frankfurt 1971 Nemesis 1972 Elephants Can Remember 1973 Postern of Fate 1974 Poirot's Early Cases (eighteen short mysteries) 1975 Curtain (Poirot's last case, written four decades earlier) 1976 Sleeping Murder (Miss Marple's last case, written four decades earlier) Agatha Christie also wrote 6 romantic novels under the pseudonym Mary Westmacott. She wrote nonfiction as well - four books including an autobiography and an entertaining account of the many archeological expeditions she shared with her second husband, Sir Max Mallowan. Interesting to note that her books have sold over a billion copies in the English language and another billion in over 45 foreign languages. She is outsold only by the Bible and Shakespeare (as of 2003).