Continuity mistake: When the men first enter the spaceship, one of the windows shows an afternoon sky and the one next to it shows a nighttime sky. (01:11:20)
Continuity mistake: Frederick picks up a bottle of champagne out of the ice bucket and shakes it a little. As he does this the foil and wire are still on top. He turns and aims the bottle at his wife, then tips it back and the foil has vanished as he now just removes the wire and cork.
Continuity mistake: After Sir Hugo has stabbed the girl on the moor, no blood is visible on the knife he used, however after he drops it (because he is attacked by a hound) blood has now appeared on it.
Continuity mistake: The doctor just killed Mr. Fleming. Cut to Agnes Moorehead playing cards; She is casting no shadow on the desk from the side view, but in the view with the camera in front of her, she is projecting a shadow. (00:11:35)
Continuity mistake: Christopher Lee looks outside his useless nephew's room and spots two hot Swedish girls. Renato Rascel has a bottle of wine in hand and walks towards him, but the bottle is gone when he tries to stop him. (00:23:40)