Revealing mistake: Halfway through the movie, Alta is swimming in the pond, supposedly nude. However, when she climbs out, she can be seen wearing a flesh-covered swimsuit. (00:45:15)
Suggested correction: Alta never said she was naked. She didn't know what a bathing suit was and Adams assumed she was naked.
Revealing mistake: A couple cross the road to enter Victoria Coach Station, London. There is the noise of a coach braking hard and they throw themselves away from a coach just inside the entrance, which obviously was not moving at the time. They walk into the station and talk to an inspector, while the same coach is driven out of the entrance past where it is supposedly parked.
Revealing mistake: During the interrogation after the Albert Hall assassination attempt, the telephone used is an obvious Western Electric American-made phone instead of a British-manufactured telephone, betraying the fact that the interiors for the movie were shot in Hollywood.
Revealing mistake: Toward the end of the film, when Claire Anderson enters the cave where the monster is waiting, she passes a distinctive rock formation. In a later scene, where she is going further into the cave, she again passes the same rock formation.