The dentist was found with a blackened hole below his right temple. A pistol lay on the floor near his outflung right hand. Later, one of his patients was found dead from a lethal dose of local anaesthetic. A clear case of murder and suicide. But why would a dentist commit a crime in the middle of a busy day of appointments?

A shoe buckle holds the key to the mystery. Now � in the words of the rhyme � can Poirot pick up the sticks and lay them straight?

Agatha Christie was born in Torquay in 1890 and became, quite simply, the best-selling novelist in history. Her first novel, The Mysterious Affair at Styles, written towards the end of the First World War, introduced us to Hercule Poirot, who was to become the most popular detective in crime fiction since Sherlock Holmes. She is known throughout the world as the Queen of Crime. Her books have sold over a billion copies in the English language and another billion in over 100 foreign languages. She is the author of 80 crime novels and short story collections, 19 plays, and six novels under the name of Mary Westmacott.