Starring: David Suchet, Hugh Fraser, Philip Jackson, Pauline Moran
Factual error: Poirot is cycling through Wimbledon; he passes by a house which has a definitely non-1930 car in the yard, and a yellow alarm box on the first floor. (00:18:20)
Factual error: To meet The Veiled Lady the second time, Hastings and Poirot go to the Natural History Museum. The establishing shot is the iconic "Dippy the Diplodocus", right in the main hall. But in 1935, Dippy would have been in the reptile hall instead, and with his head and neck mounted differently. (00:37:35)
Plot hole: The hole in the hat was pre-existing and the bullet was fired in advance and dropped. Poirot notices immediately the hole when Nick puts the hat down but somehow missed it while she was wearing it as she supported him. He also does not notice that the bullet has not been fired at that time - which would have been still hot if just fired, not at all if dropped. Most importantly, in the spot where they were sitting, it's not even possible to think where a shooter could have ever been hidden; nobody wonders where the mysterious shooter could have been or cares to investigate the circumstance despite knowing the very moment the supposed shot happened. The fact is basically ignored throughout the rest of the episode.
The Disappearance of Mr. Davenheim - S2-E5
Hercule Poirot: And please, do not fraternize with that creature. I am still training him.
Captain Hastings: It's only a parrot.
Hercule Poirot: I was talking to the parrot. (00:27:00)
Trivia: Poirot in the ship's lounge is reading the actual May 1st 1935 issue of Bystander (recognizable by the cover and with the correct page order, does not seem to be a simple movie prop), roughly consistent with the time frame of the first season and a contest taking place on the 14th. (00:07:50)
Question: Why does Poirot claim to be an American citizen when being interrogated by customs?
Answer: It sounds a bit like "American", but listen very closely and you will hear "Belgian".
Answer: He definitely says "Belgian", but the subtitles get it wrong and show him saying "American."
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