Continuity mistake: Blore is shaving. Suddenly something occurs to him and goes to the door calling Lombard. He has still bits of shaving cream all over his cheek; despite being still crouched by the door, after a brief cut to Lombard approaching, his face (in particular the sideburn who had still abundant cream on it) is practically clean. (00:58:00)
Continuity mistake: In the scene preceding Emily Brent's death, Judge Francis J. Quincannon moves his glasses around, creating a couple of obvious discontinuities, first when his hands from distanced become joined at the very beginning, and then at the bottom of the stairs when he waves Blore to stay put. (00:58:50)
Continuity mistake: When Emily Brent is found in her room, the light of the area changes between shots - just look at the direction the legs of the first responder cast a shadow at. Also, the position of his feet is different; he already almost reached the door in the previous shot, and is 2 boards behind in the new one. (01:00:10)
Continuity mistake: When Lombard tells Vera "Don't you think it's strange that there's never a third person present when anything unpleasant occurs?" his cigarette is in the left hand, and switches instantly to the right in the next shot. (01:03:35)
Continuity mistake: When the Doctor and the Judge realise that they are on their own at the billiard table, the Judge holds his cue stick towards the left, right, left. (01:05:25)
Continuity mistake: Dinner after Quincannon and Armstrong bonded at the pool table. The Judge says "Very well, I shall begin." Blore is still using the cutlery on his plate, but he has both hands off the table at the cut. (01:08:25)
Continuity mistake: Blore gets up irate after Quincannon and Armstrong's confessions; the Judge next to him had both hands on the table, but he has just the right one in the new shot. (01:09:30)
Continuity mistake: When the Judge asks Blore to confess saying "We're listening, Mr. Blore", Blore is clutching the napkin. As he begins to speak in a new shot, the cloth is gone from his hand. (01:09:50)
Continuity mistake: The doctor is watching the others when Lombard says he heard a shot. The close-up on Walter Huston shows him with a totally different facial expression compared to the previous and following shots, and the shadow he casts on the wall is also different (it's also incongruous, since in theory the only light comes from either his candles or those from others in front of him, but he projects a shadow to his side/front). (01:13:35)
Continuity mistake: When the doctor proclaims the Judge dead, Lombard and Bloor's position on the door changes - they are close together, then more distant, then shoulder to shoulder again. (01:14:30)
Continuity mistake: Lombard is protecting Vera's door, preventing the doctor from entering. Armstrong says "Oh but you will, you will." You can notice the double shadow projected by him, and Lombard's more marked but single one, mostly into the frame and not the actual door. Nobody moves candles of any kind in the next seconds, but when Armstrong after his explanation gets again in Lombard's face, Lombard is projecting a big shadow on the door and Armstrong none. (01:16:40)
Continuity mistake: Inside Vera's room, she retorts "What about me?" when Lombard tells her his theory about who Mr. Owen is. The shots have different lighting, with either an overwhelming shadow from Lombard on her, or barely any shadow at all. (01:20:05)
Continuity mistake: During the confrontation between Vera and Lombard at the beach, their hair is windblown with intensity that changes at every cut. (01:29:05)
Continuity mistake: On the beach, Vera and Lombard are quite literally pointing fingers at each other...except they are not; new shot, different pose. (01:29:10)
Continuity mistake: When the 'sole' survivor walks into the supposedly empty house and spots the noose, it is placed quite high. When they walk back into the room with Owen, the noose is dangling low enough to nearly brush against his head. (01:31:35 - 01:32:25)
