Visible crew/equipment: Captain Hastings has his microphone wire on show (when placing his hand in his pocket).
Visible crew/equipment: At the very end of the episode, as Poirot's car drives off headed to the harbor, filming equipment is neatly reflected in the door. (00:51:40)
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 Tragedy at Marsdon Manor - S3-E6
Samuel Naughton: Was the accomodation all right?
Hercule Poirot: No, monsieur Naughton. The accomodation was all wrong.
Samuel Naughton: Oh...
Hercule Poirot: The duck-feather pillows. It feels as if the duck are still in them. (00:14:50)
The Disappearance of Mr. Davenheim - S2-E5
Trivia: David Suchet performed all the various conjuring tricks Poirot is trying to pull off. The illusionist in the theater show at the beginning is the late Patrick Page, real life stage magician and coach/consultant for the episode.
The Murder of Roger Ackroyd - S7-E1
Question: The doctor (James) put on a Dictaphone to make the suggestion that Roger Ackroyd was alive at 21:30 hrs. But how could he know that someone (Paton) would pass the door of Ackroyd's study at precisely that moment?