From IMDB:

In Agatha Christie’s most twisted tale, a spy-turned-private-detective is lured by his former lover to catch her grandfather’s murderer before Scotland Yard exposes dark family secrets.

From Netflix you can stream this 2 hour complete film.

Both aging actors and young players unite to produce a classic  but somewhat dull and badly acted Agatha Christie mystery story. Among the aged are Glenn Close (elegant and beautiful),  Gillian Anderson (tired in a really ugly black wig), Terence Stamp (what an immense resumé) , and Julian Sands.  Gillian Anderson has done herself no favor with her exaggerated (embarrassing?) performance.

Except for finally learning which of these awful people is the killer, there is not much to gain is watching this sad, mediocre work.