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)
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)
Answer: He definitely says "Belgian", but the subtitles get it wrong and show him saying "American."
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