Continuity mistake: Hastings sits down when Japp is having his meal at the inn, and eats one of Japp's sandwiches. In the rest of the scene, the sandwiches on the plate change position and Japp's beer has been replenished a bit. (00:35:00)
Continuity mistake: When not-so-Lavington is spying Japp and Mad Dog Poirot outside of the station, he is holding the wheel with his right hand at the top, but a moment after he's using that hand to smoke instead. (00:34:35)
Continuity mistake: Poirot opens the "intolerable" letter Miss Lemon hands him; camera in the door and he has his finger between envelope and letter, reverse shot and he is holding them parallel together. (00:33:45)
Continuity mistake: When the box opens revealing the jewelry, the jewelry is scattered differently each time it is seen. The box itself gets closer to the table's edge when the lady nabs the jewelry. (00:40:40 - 00:42:40)
Continuity mistake: Poirot and Hastings are talking with Freddie, by her invitation. She says "You'll be giving me a diploma next" and three extras walk by her chair. In the following shot she completes the action of standing up, but the extras are still there, behind their original positions. (00:44:15)
The Disappearance of Mr. Davenheim - S2-E5
Continuity mistake: Carving the distant relative of his parrot for dinner, Poirot slices one side in the close-up, which turns out to be the exact opposite side in the wider shot. (00:38:35)
Continuity mistake: Lavington puts his hat on the couch before talking to Poirot. The hat shifts closer to Hastings and then back closer to the armrest during the scene. (00:12:45 - 00:14:30)
Continuity mistake: Lavington arrogantly sits in Poirot's study and opens his cigarette case, closing it after. In the following close-up, the case is open again. (00:13:15)
Continuity mistake: Poirot reads the telegram after the opium den raid. The letter is in his left hand, but moves between shots to the right hand. (00:40:40)
The Disappearance of Mr. Davenheim - S2-E5
Continuity mistake: When Poirot's castle collapses, the cards are all in perfect order, but become scattered after the cut to Japp. (00:35:40)
Continuity mistake: The level of sherry in Radnor's glass changes after Hastings smiles at him when Poirot is laying the trap. (00:38:40)
Continuity mistake: After reading the will of the deceased, the lawyer folds back the first page twice in two different shots. (00:26:05)
Continuity mistake: When Freddie holds the Mauser 1910 gun, Alison Sterling holds it in a very characteristic way (thumb and and pinky finger stick out) in the front views. It is held in a much more orthodox way in the views from behind. (00:43:50)
Continuity mistake: Starting the seance, Poirot ask everyone to hold their hands. Lazarus barely stifles a laughter. Between that shot and the previous, his hand goes from above the table to underneath it. (01:38:25)
Continuity mistake: Miss Lemon's ice cream quite literally melts between shots (and the actress ignores the dripping on her fingers). (00:51:15)
Continuity mistake: When Poirot shows Freddie the bullet, in the close-up his hand is right by the sugar bowl, but he was shown putting the cigarette holder at greater distance, closer to Freddie herself. (00:25:05)
Continuity mistake: Poirot shows Hastings Nicki's hat; he holds it in a different way (using the thumb to pinch, or with the light brim tucked in between index and middle) between shots. (00:08:55)
Continuity mistake: Poirot and Hastings are eating after their first visit to End House. During the entire scene, natural light changes in intensity depending on the angle of filming. (00:20:15 - 00:21:10)
Continuity mistake: During the sentence when Hastings tells Poirot he's got "No imagination at all", the lady sitting behind the Belgian faces the other way between shots. (00:02:25)
Continuity mistake: When Japp talks to Poirot and Hastings about the gallery troubles, the peppermint rock candy he is waving is wrapped differently between shots. (01:13:40)
Answer: He definitely says "Belgian", but the subtitles get it wrong and show him saying "American."
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