Murder on the Orient Express is a detective novel by Agatha Christie. While returning on the Orient Express to London, detective Hercule Poirot meets a misanthropic American named Mr. Ratchett. After Mr. Ratchett is murdered on the train, Poirot is hired to solve the mystery, discovering that Mr. Ratchett is actually the kidnapper and child-killer, Cassetti. He also learns that everyone in coach class had some reason to kill him and, in the end, discovers that everyone was complicit in the murder.
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