This film is one of my all time favourites. <br /><br />As an Agatha Christie fan I am carefully critical about adaptations of her works. The screenplay is as good as one of her better novels; it makes a seamless transition from book to screen, eliminating some subplots and more minor characters (e.g. the Allertons) in order to achieve a flowing and 'easy to understand' plot with no holes. <br /><br />The choice of Peter Ustinov as Poirot was inspired. His Poirot is distinctly recognisable as that from the books but the talent and ability of Ustinov shines through. Albert Finney would not have been as good in this film.<br /><br />The supporting cast is brilliant. Each gives a performance that makes you wish they were on screen for longer; Angela Lansbury as a drunken novelist, Mia Farrow as a cold calculating murderer, etc.. One of the best is the young Simon MacCorkindale, for whom this was his breakthrough film (he is currently Consultant Harry Harper in BBC One's Casualty, for UK readers), as the man torn between love and then led to murder. Also David Niven gives an especially strong performance as Colonel Race.<br /><br />All in all; it is, in typical Christie fashion, a satire on the lives of the upper class that is buoyant with snippets of humour and romance as well as the inevitable murder (or rather four and a suicide). The score is very good too and the movie has a good old straight backed stiff upper lip feeling to it that makes it a pleasure to watch and makes one wish they could be there themselves.