Factual error: The Seaview's military history computers need an upgrade. The derelict German sub is identified as a WWI ship, the U444, supposedly sunk in 1918. There were only 167 U-boats in WWI. U444 wasn't built until 1942. And the sub's design is definitely WWII, not WWI. (00:02:30)
Visible crew/equipment: When Nelson says, "Let's get out of here," the shadow of the entire camera rig moves by on the side of the navigation console. (00:07:45)
Factual error: The derelict sub is said to have suddenly moved itself more than 30,000 sea miles from its original position. This makes no sense. The entire circumference of the Earth is only 22,000 sea miles. And if the sub had somehow circled the globe plus an additional 8,000 sea miles, there'd be no way to tell that it hadn't simply moved just 8,000 miles. (00:08:10)
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)
