Whilst Poirot – as always played for ITV by the great David Suchet – is pre-occupied with investigating the strange and gruesome murder of an elderly psychiatrist, his old friend, the crime writer Ariadne Oliver – Zoë Wanamaker – has a case of her own to solve.
She is pressed by the loathsome Mrs Burton-Cox (Greta Scacchi) to uncover the truth of two decade-old deaths; were they murders or a double-suicide?
And if it was murder then who killed whom? Did General Ravenscroft (Adrian Lukis) shoot his wife, Margaret (Annabel Mullion), Ariadne’s old school chum, or did Margaret shoot him?
In spite of Mrs Burton-Cox’s impertinence, Ariadne can’t help but be curious, and she takes it upon herself to set matters straight when her god-child, Celia (Vanessa Kirby), the dead couple’s daughter, begs her to uncover the truth.
However, Poirot’s skills remain engaged elsewhere, as the case of the dead professor twists and turns, with Poirot reluctant to accept that his good friend, the psychiatrist’s son, Doctor Willoughby, is himself responsible.
So Ariadne sets off on a journey into the past to dig for the facts, but theories abound as memories get muddled and old secrets remain stubbornly hidden. Before long though, the old Ravenscroft puzzle is pulled sharply into the present-day, when the life of Desmond (Ferdinand Kingsley), Mrs Burton-Cox’s son and Celia’s intended, is threatened by a mysterious figure in black…
Poirot’s already twitching mind is immediately piqued, and when he realises the murder of his old professor is connected with Mrs Oliver’s investigation, they join formidable forces.
With the help of the great detective’s little grey cells, a trip to Paris, a wig-maker and the evidence of a clever dog, Poirot manages to penetrate the fog of memory to uncover the truth of two long-ago deaths, and how that tragic story inspired the vengeful present-day killer whom he himself has been hunting…
Agatha Christie’s Poirot: Elephants Can Remember, 9th of June at 8pm on ITV