The two-part serial was adapted by Sarah Phelps from Agatha Christie's short story and directed by Julian Jarrold, airing on BBC One over Christmas 2016.

Unlike previous stage, film and television adaptations, including Billy Wilder's 1957 film version, this serial restores the original ending of Christie's short story.

Sarah Phelps' adaptation makes the First World War the emotional lynchpin of the whole story, a thematic addition noted by critics as a major achievement.

Critic Gerard O'Donovan of The Daily Telegraph praised Andrea Riseborough as the 'star of the show' for the blend of damage and menace she conveyed in her performance.

O'Donovan highlighted that the BBC adaptation's biggest coup was reverting to Christie's original twist ending while considerably expanding upon it, giving the story greater depth and contemporary resonance.

Toby Jones' performance as solicitor John Mayhew was singled out by reviewers as superb and credible.