Watch Masterpiece Mystery online: Episode 1 Hercule Poirot, Series XI: Three Act Tragedy

Murder takes center stage when an eclectic cast of characters attends a deadly party, and Poirot must investigate not one death, but two. -- When a guest drops dead at a cocktail party, Hercule Poirot sees no evidence, no motive, no method and no murder...until another party yields another death. -- When an elderly Cornish vicar suddenly drops dead at a party, everyone looks to fellow guest Hercule Poirot to solve the murder. But the Belgian super-sleuth sees no foul play, correctly predicting that analysis of the clergyman's glass will yield nothing more than the remains of an excellent dry martini. Before long, however, Poirot is summoned back to England from his boredom among the palms and irksome children of Monte Carlo. Another death among the same revelers has occurred, this time, indisputably, murder. With the help of two enthusiastic amateurs — his old friend, the retired stage actor Sir Charles Cartwright, and Charles's jaunty love interest, Miss "Egg" Lytton Gore, Poirot questions the dramatis personae, as Sir Charles calls the party guests. And as Sir Charles embraces his role, donning a pair of patent-leather spats, Poirot works to unravel a perplexing mystery, building a house of cards, tracking a missing butler, and even hosting his own sherry party — "That is a fashionable thing to do, n'est-ce pas?" David Suchet portrays the fastidious detective Hercule Poirot, with Martin Shaw as Sir Charles Cartwright and Art Malik (Upstairs Downstairs) as Sir Bartholomew Strange, in this adaptation of Agatha Christie's novel.

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