Continuity mistake: Frankenstein buys a sprig of freesias as a buttonhole: two yellow flowers and a purple. The sprig immediately changes into two purple flowers and a yellow. When Frankenstein meets Mrs Brandt and they go into the drawing room, the flowers are two purples and a red with yellow centre. Once in the cellar to see Mr Brandt, the red goes, and a yellow is back with two purples. (00:57:45 - 01:03:55)
Continuity mistake: Inside Moon City, artificial gravity is cited to explain why everything behaves as if under a full Earth gravity. And yet, in scenes out on the untamed lunar surface, everything is still behaving as if under a full Earth gravity.
Continuity mistake: The Russian spaceship approaches the stranded 'Ironman 1' capsule, and as it moves across and fills the screen, it blocks the bright sun directly behind it. The following shot shows it moving away from that position and the sun is now nowhere to be seen.
Continuity mistake: When Carl lets his dog out of the bag, in the close-up there's a shadow on Rod Steiger's boot, and a shadow of something or someone standing between him and the camera: both are gone in the following shot, when the dog runs across the lawn (and 'knocks aside' the camera). (00:08:20)