Agatha Christie had been quite displeased with some film adaptations of her works made in the 1960s, and accordingly was unwilling to sell any more film rights. When Nat Cohen, chairman of EMI Films, and producer John Brabourne attempted to get her approval for this film, they felt it necessary to have Lord Mountbatten of Burma (of the British Royal Family and also Brabourne’s father-in-law) help them broach the subject.
In the end, according to Christie’s husband Max Mallowan, “Agatha herself has always been allergic to the adaptation of her books by the cinema, but was persuaded to give a rather grudging appreciation to this one.” Christie’s biographer Gwen Robyns quoted her as saying, “It was well made except for one mistake. It was Albert Finney, as my detective Hercule Poirot. I wrote that he had the finest moustache in England — and he didn’t in the film. I thought that a pity — why shouldn’t he?”
via wikipedia






