Hercule Poirot manages to get a berth on the glamorous Orient Express, which is unusually crowded for the off season. He joins an international cast of passengers on the train, one of whom attracts his attention - a smartly dressed, obviously wealthy American. The next day the man tells Poirot that his life has been threatened and offers the detective "big money" if he will protect him. But there is something about the man Poirot doesn't like, and he refuses the offer.

The next morning the man is found dead in his cabin, stabbed twelve times. There is no lack of clues for Hercule Poirot - but which is real and which a clever plant? Poirot realizes that this time he is dealing with a murderer of enormous cunning and that, in a case fraught with fear and inconsistencies, only one thing is certain - the murderer is still aboard the train and waiting to strike again.

Agatha Christie's famous mystery is dramatized with a full cast starring John Moffatt as Poirot, and including Joss Ackland, Sylvia Syms, and Francesca Annis.