<P> In Belgrade, on the second night of the journey, two extra coaches are added to the train and M. Bouc he gives up his first - class compartment to Poirot and moves to a different coach himself . That compartment adjoins Ratchett's . The train is stopped by a snowdrift near Vincovci (sic). Among the several events that disturb Poirot's sleep is a cry from Ratchett's compartment . The next morning, M. Bouc informs him that Ratchett has been murdered and asks Poirot to investigate . </P> <P> When Poirot and Dr. Constantine examine Ratchett's compartment, Poirot finds a note with the words' - member little Daisy Armstrong' on it, which leads him to doubt Ratchett's identity . A few years before, three - year - old heiress Daisy Armstrong was kidnapped by a man named Lenfranco Cassetti, who collected a ransom and killed the child . Cassetti was caught but fled the country after he was acquitted on a technicality . Poirot concludes that Ratchett and Cassetti are one and the same . </P> <P> Poirot proposes two possible solutions: either that a stranger boarded the train and murdered Cassetti, or that every one of the passengers, who had a connection to the Armstrongs, had all conspired to kill Cassetti together . The ostensible Mrs. Hubbard, in fact Daisy Armstrong's grandmother, the famous actress Linda Arden, confesses the truth of the second solution, yet M. Bouc and Dr. Constantine choose to present the first of the two to the Yugoslav police . </P> <P> The Times Literary Supplement of 11 January 1934 outlined the plot and concluded that "The little grey cells solve once more the seemingly insoluble . Mrs. Christie makes an improbable tale very real, and keeps her readers enthralled and guessing to the end ." </P>

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