Factual error: The diving bell descends to 4000 feet, where no light can penetrate and the ocean around them should be pitch black. But some strange, unseen phenomenon is lighting up the bell quite nicely for the camera. (00:21:15)
Deliberate mistake: Several of the roaming dinosaur segments here are repeated 2-3 times over. They're all recycled footage from producer Irwin Allen's own 1960 remake of "The Lost World," and Allen must have wanted to get as much use out of the dino shots as possible. (00:28:00)
Other mistake: One of the natives putting the captured Seaview personnel into the cave is wearing laced up sneakers. (00:36:25)
