Evil Under the Sun

Evil Under the Sun is a 1982 British mystery film based on the 1941 novel of the same name by Agatha Christie. It was directed by Guy Hamilton, and stars Peter Ustinov in his second theatrical appearance as the Belgian detective Hercule Poirot.
A hiker finds a dead woman on the Yorkshire moors; the victim, who has been strangled, is identified as Alice Ruber. Shortly afterwards, Belgian detective Hercule Poirot examines a diamond belonging to millionaire industrialist Sir Horace Blatt , and declares it a fake. Assured that Sir Horace gave a real diamond to his mistress and she later returned the fake to him, Poirot agrees to meet Sir Horace at an exclusive Adriatic island resort to confront her. The hotel is the former summer palace of the reigning King of Tyrania, now owned by Daphne Castle , who had received the palace "for services rendered".

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