The Mysterious Affair at Styles - S3-E1
Continuity mistake: Poirot is concentrating in London, making a house of cards. When he says "I steady my nerves, that is all", the 6 of hearts can be seen in his right hand, and he sets it as the diagonal piece. Cut to Hastings, and then Poirot supposedly still has the same house in front of him...but it is not. Where the 6 of hearts was, there is now a 6 of spades, and the whole castle is different, with the cards pulled tighter together. Later he rebuilds the house, and he sets horizontally in the close-up a 5 of spades, which turns into the 2 of spades immediately after. (01:19:40)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: The guests of Styles Court manage to get inside the room of Mrs. Inglethorp and talk to her before the second fatal crisis happens. In the first wide shot you can see Hastings peek at Lawrence and then look towards the fireplace, which is an action he'll do in the close-up that follows - Lawrence does not seem to look in the direction Hastings is checking out, at all, but that is actually a nice touch considering the resolution. Moreover, in the second close-up of Hastings looking at him (the one that follows the view of the fireplace), Mary is directly in front of Hastings, you can see her insignia and arm. But instantly she is shown at the cut, creeping along the wall behind Lawrence. (00:29:00)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: At dinner, Alfred Inglethorp asks Hastings what he's going to do after the war. The person to his left is placing a glass on the table. The next cut happens mid-sentence and in that instantaneous timeframe the glass is perfectly still while the wine was still noticeably moving in the previous shot. (00:10:10)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: The coroner asks Mary to tell everyone about the quarrel. Frontal shot of Mr. Wells; he is pointing his hand with the spectacles at a certain height. Reverse shot; the hand is lower, resting on the other hand, and only then he raises it to the same level as it was in the other shot. (00:53:40)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: When Evie Howard leaves the house after the argument with Mrs. Inglethorp, she sits on the sofa explaining what happened to Hastings and the others. She has her hands on top of the purse handles. After a brief cut on Mary saying "oh no", one of the handles is free. (00:16:40)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: About the burnt will, the lawyer asks the obvious question to John Cavendish "Are you so sure it's a coincidence?" He's holding in his raised left hand a sheet. Next shot and he has both hands down on the desk. (00:48:55)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Cynthia is sobbing with Hastings, and he asks her to marry him. The handkerchief in her hand changes position between shots (particularly easy to spot when you look at the black band). (01:13:05)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: After Hastings reminds him of the mantelpiece, Poirot shouts "Mon Dieu!" and pounds the table. The cards scattered on the table differ in disposition between shots when he stands. (01:21:05)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: When Hastings spots Poirot from the window as he arrives for the denouement, his hand is in a different position on the window frame (left or right of the vertical bar). (01:26:55)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: At the hearings, the doctor is on the stand and says "There was no strychnine in it." Mr. Wells closes his fountain pen. But then in the next shot he holds it in his hand. (00:52:40)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Poirot locks the document case in a close-up. The shadow on the case is at the center of the object, but in the wider shot it is projected entirely on the left side. (00:38:15)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Mrs. Inglethorp's death happens with her having a much messier hair and the neck tilted to an angle in the wider shot, compared to the close-up on Gillian Barge. (00:30:00)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: When Hastings tries the fake beard on, it sticks past his fingertips more in the shots from behind than on the front. (01:09:15)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: The larger broken porcelain pieces Poirot is examining in front of the fireplace change place between shots. (00:39:45)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Hastings has just met the Ingelthorps, and now is outside so John Cavendish can introduce his wife. In the wide shot it's evident that John lowers his arm, but in the closer view his arm is still held up high before Mary speaks. (00:08:10)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: The first time Mrs. Ingelthorp is shown, she is holding a pen. In the second shot she is holding it in her right hand, while in the third she has the lid of the pen in the right hand and the pen itself in the left. (00:07:30)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Hastings receives the messages that he is wanted by someone outside the movie room; you can see the person sitting next to him turn towards him in the first shot, and re-turn towards him in the following. (00:02:25)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Everyone is silent at dinner after Miss Howard left, but Mr. Inglethorp keeps a healthy appetite. As he eats, look at his plate; the shadows cast on it switch side depending on the camera angle. (00:18:40)
The Mysterious Affair at Styles - S3-E1
Continuity mistake: Mary Cavendish's wine glass goes from almost empty to full and vice versa several times during the dinner scene the first day. (00:10:10 - 00:11:10)
