Plot hole: The Seaview's crew have a wild shootout aboard ship, and their bullets are seen to go all the way through a 6-inch-thick hatch door. Gee, you'd think that somewhere during their military training, somebody would have taught these guys why firing high velocity weapons on a submerged submarine is a really bad idea. (00:38:15)
Continuity mistake: The shot from the rear of Kowalski and Nelson shows Kowalski holding the scanner. The next scene Nelson asks Kowalski what is on the scanner and then tells Kowalski to pick it up.