Kind Hearts and Coronets (Robert Hamer, UK, 1949)

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At once a witty comedy of manners, a grotesque serial-killer caper and an acerbic satire on the class system.
— Time Out

Louis Manzzini (Dennis Price) a distant - & poor - relative of the Duke of D'Ascoyne, plots to inherit the title by murdering all eight other heirs who stand ahead of him in the line of succession (all played brilliantly by Alec Guinness). Out of the 80 films shot by cinematographer Douglas Slocombe, Kind Hearts and Coronets was one of his personal favourites.