Plot hole: In the original novel, the victim's voice is described as "shrill." In here, it's quite the opposite. When the trick for the alibi is performed, the relevant lines are not read by John Normington, thus Poirot's exposition at the end, with the girl providing the voiceover, indirectly further exposes its unbelievability.
Agatha Christie's Poirot (1989)
1 plot hole in Problem at Sea
Starring: David Suchet, Hugh Fraser, Philip Jackson, Pauline Moran
The Adventure of the Egyptian Tomb - S5-E1
Factual error: In the scene after Poirot pretends to be poisoned, a person folds the modern flag of the Arab Republic of Egypt instead the flag of the Kingdom of Egypt as it was at that time.
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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