Here is the trailer for the second series:  

After 25 years playing the Belgian detective, David Suchet is preparing to say goodbye to Hercule Poirot as the iconic character attempts to solve his final case on the small screen. source: bbc.co.uk by Emma Saunders, November 14th, 2003

Beulah Maud Devaney  argues that ITV's hit period drama written by Julian Fellowes may have been inspired by Isabel Colegate's novel  The Shooting Party (1980) , or at least its film adaptation (1985).

Link source: The Guardian NB: ITV = commercial television network in the UK