Who's the village killer?

We travel back to the 1950s for a new two-part adaptation of Agatha Christie's Murder Is Easy, as diplomat Luke Fitzwilliam (Industry star David Jonsson) learns of a series of murders in sleepy Wychwood under Ashe from fellow train passenger Miss Pinkerton (Downton Abbey star Dame Penelope Wilton).

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Other villagers dismiss the deaths as accidents, but Miss Pinkerton is confident that there's a killer on the loose - and when