I noticed that two of the three user reviews have confused this 2006 PC game in which David Suchet provided the voice of Poirot with his 2010 BBC version which was a very dark and far-afield version of the story. While that version has been praised for daring to be different, a lot of people who view Suchet as the definitive Poirot I suspect were hoping to see him do the most famous of all Poirot stories in a traditional way. That's because for all the style and glitz of the 1974 movie and its great all star cast, time has not IMO been kind to Albert Finney's performance as Poirot, who seems far too eccentric in the role.
Those disappointed by the 2010 version will find this PC game done four years earlier fascinating because you get to hear Suchet doing a traditional version of the story. The game faithfully adapts the story and draws from the novel and the 1974 movie version but throws in some twists for the benefit of those who know the story. Rather than having the gameplayer act out Poirot, the gameplayer becomes a new character for the story, Antoinette Marceau, a representative of the line who gets Poirot aboard (she takes the place of Monsieur Bouc, who is referred to as her superiority). Because Poirot is injured when the train stopped abruptly, the player as Antoinette does all the legwork of interviewing the suspects and being forced to handle new challenges unique to the game and then report back to Poirot for guidance (Suchet BTW really shows how he is in a class of acting beyond the voice artists used for the other roles. Some of them, like the voice of Countess Andrenyi sound downright embarrassing). In the end, it is still Suchet as Poirot who gets to deliver the "classic" ending of the story to the assembled suspects (which we did not get to see him do in the BBC version) but wait, there's actually one final unexpected twist, a "third solution" that i think will surprise first-time players of the game and it in the end manages to work perfect in the context of the traditional version of the story.
The game play requires many hours to get through but it's not too difficult. I recommend it to Christie fans for the thrill of hearing Suchet do Poirot the "right" way in this story in contrast to the off-beat version of the 2010 BBC filmed adaptation.
