Continuity mistake: Mr. Ferguson and Rosalie Otterbourne say goodbye to Poirot; Ferguson is holding a suitcase in his right hand, but when Poirot says one last thing to them, the suitcase disappeared mid-stairs. (02:17:15)
Continuity mistake: Inside the saloon, Poirot says he knows who killed the three victims. Maggie Smith is looking at him, her left forearm raised. In the reverse shot, her arm is down. (01:52:55)
Continuity mistake: The 'moray eel' on Poirot's plate is shown in close-up. The garnish is on the left side of the plate. In the wide angles though (and at one point Poirot lifts the plate, so we get a good view) the plate is turned differently, the garnish being on the side opposite Poirot's seat. (01:43:00)
Audio problem: During the dinner scene when Poirot finds an eel in his plate, the quartet plays a song in perfect classical music, but they are using instruments typical of the local folklore. A rebec does not sound like a violin. (01:42:55)
Continuity mistake: Poirot uncovers the dead body in the ice cellar; he does not touch the body anymore, but the hair is scattered on the table in a different position when Race retrieves the pearls. (01:36:45)
Visible crew/equipment: Poirot and Race pass by the camera to reach the top deck and investigate the noise they heard after the attempt on Poirot's life. When they go up the stairs, you can see a shadow from the camera equipment go slightly up when the camera goes up with them. (01:28:20)
Revealing mistake: When a dangerous cobra threatens some stand-in wearing Poirot's pants, under the sink you can see the reflections on the protective glass. (01:25:50)
Continuity mistake: Poirot enters his bathroom to freshen up. There's a brush on the left side of the sink, placed on top of a box. When the cobra sticks its head up, the brush rests directly on the sink. (01:25:40 - 01:26:05)
Continuity mistake: When Jane Birkin is talking to Poirot in French, David Niven is leaning against the back of her chair with his hand. Cut, and he's watching her with his arms crossed. (01:22:05)
Continuity mistake: When Poirot and Race enter the doctor's room to check on Simon Doyle, they find him unconscious on the bed. There's a shelf behind the bed with a few books and amongst them the cable of the bedside lamp switch, all tangled up. They revive Doyle, and the cord with its switch dangles off the shelf, on the pillow. Throughout the whole scene now, the cable and switch keep getting on/off the shelf. (01:19:50)
Continuity mistake: Jacqueline moves towards Poirot at the end of the interview with Bowers; her vest is open in the first shot, but in the second, consecutive shot she has her hand in her pocket and her other arm across to keep it closed. (01:17:40)
Revealing mistake: After Poirot has inspected the messier of the 2 bottles of nail polish he has a laugh with Race (it almost looks like Ustinov and Niven are breaking character at the end of the shot) and they briefly pass through the murder scene again. Look at Lois Chiles' eyelashes; she's blinking, not quite dead. (01:12:20)
Continuity mistake: When the doctor leaves Linnet's room saying he's outraged by Poirot's allegations, the cabinet to the left is closed, but in the reaction shot on Poirot and Race (and in the rest of the scene) the cabinet is open. (01:11:35)
Revealing mistake: When Poirot gives the sarcastic explanation of the letter J to the doctor and colonel Race, the chest of the stone-cold dead Linnet quietly rises and falls as the very alive actress breathes. (01:08:35)
Continuity mistake: In the longshot where the maid approaches Mrs. Doyle's cabin, the shadows of the deck above reach just the highest part of the starboard cabin doors. When she shouts and runs to get help, the shadows cover the whole louvered top half of the doors. (01:06:50)
Continuity mistake: When the doctor creepily shuts the door behind him to have a tete-a-tete with Linnet, in the side view his hands are in front of his belly, in a stance entirely different from the front view where his arms are down his sides. (00:53:25)
Character mistake: Dr. Bessner tells Linnet that the Eastern statue she'll see at Abu Simbel is 'the vocal statue', which emits a sound at sunset. The statues the doctor mentions are the Colossi of Memnon, over 500 kms north of Abu Simbel, so the movie here mixes up two very different monuments. (00:49:30)
Deliberate mistake: Poirot riles up Pennington narrating the story of Grand vizier Ptahhotep who was crushed under the weight of the silver he embezzled. It's a lovely moral story, but Ptahhotep was actually a virtuous administrator and is credited (with various caveats) with writing "The Maxims of Ptahhotep", one of the first books in human history, and there's no record of such a story. It's likely that Poirot made that part of the story up counting on Pennington's ignorance on the subject. (00:44:20)
Continuity mistake: Mrs. Ottenbourne is in the background while her daughter and the mysterious marxist are getting acquainted. She begins at one point shouting, putting an end to the conversation as Rosalie rushes to her. The rambling shout happens across two shots, and Ferguson's hand is in a different spot on the book. (00:44:00)
Continuity mistake: When Poirot and the other tourists are walking in the section of the temple of Karnak with the ram statues, they cast shadows towards the right of the screen, their left. The action focuses on Salome extolling the priapic virtues of the beasts, and the shadow she and the professor cast is at their back. (00:42:30)
