"The Mystery of the Blue Train" is a detective novel written by the renowned British author Agatha Christie. It was first published in 1928 and features her famous fictional detective, Hercule Poirot. The story revolves around the murder of a wealthy American heiress named Ruth Kettering, who is found strangled aboard the luxurious Blue Train traveling from Calais to Nice in France.Hercule Poirot becomes involved in solving the case when he meets Ruth Kettering's father, Rufus Van Aldin, who suspects that her estranged husband, Derek Kettering, is behind the murder to gain access to her...