This British show is based on books and stories by Agatha Christie, the Queen of Crime. And Hercule Poirot, her fussy but brilliant Belgian detective, was Agatha's first creation - she dreamed him up during the Great War of 1914-18 and finally killed him off in 1975, although for the producers of the Granada show (that is, this one, starring David Suchet) Poirot almost exclusively inhabits the 1930s.
Using his famous little grey cells and usually accompanied by his affable side-kick Captain Hastings (Hugh Fraser), Poirot unravels the thorniest of cases without letting a hair of his famous moustache stray out of place.
Having decided to set the show in the 1930s, Granada gave it an Art Deco theme, while the scripts preserve a lot of Agatha's witty original dialogue - and add to it in an authentic tone.
Almost sixty of the Poirot stories and books have been filmed already in this series, leaving fifteen still to go. At the present rate of four a year, the definitive Poirot should be finished by 2010.