牙醫莫利因為注射過量麻醉劑，導致病人安布理奧提斯回家之後中毒身亡，莫利因而畏罪自殺。神秘諜報員的妻子查普曼太太，被毀容棄屍在大鐵箱裡，平日慹心婦女公益活動，西爾小姐竟然是私底下卻從事諜報工作的兇手！
　　這幾宗死亡事件似乎都有合理的解釋，也有目擊者的證詞，但白羅無法忘記西爾小姐那隻脫落鞋釦的鞋子、被毀容的死者......
　　越深入調查，白羅越明瞭，死在自己診所中的牙醫莫利，雖然是謀殺事件的起點，卻只是謀殺案裡的一顆棋子。這個精明的兇手究竟是誰？是牙科診所的合夥人賴利、漂亮的金髮女秘書，還是銀行家布倫特？究竟為了隱瞞什麼事？
　　★本書中譯本《一，二，縫好鞋釦》由遠流出版
　　A dentist lies murdered at his Harley Street practice! The dentist was found with a blackened hole below his right temple. A pistol lay on the floor near his out flung right hand. Later, one of his patients was found dead from a lethal dose of local anesthetic. 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?
作者簡介
　　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.