Visible crew/equipment: When the Nautilus starts exploding after the record is played, there is a shot of things being thrown about in the chamber, and you can see the cables used to pull all the furniture to the left. (01:09:45)
Revealing mistake: Mr Hyde makes no bubbles when growling underwater. (01:11:30)
Plot hole: When we are shown the Nautilus' journey into Mongolia, are we expected to believe that this very, very long ship could travel down this river, even though it has a lot of sharp turns in it? (01:15:10)
Plot hole: When the Nautilus is in Mongolia, we are shown that there is deep snow everywhere. If this part of the movie takes place in July or August, why would there be any snow at all? Even the Yukon doesn't have snow in the summer, except for the northernmost portion of the province. (01:15:20)
Suggested correction: Mongolia is known for wildly changing weather patterns. Sudden snow or hail is common there, they are at an elevated position and is also set more than a hundred years ago.
Revealing mistake: In the mountain scene where the League is staking out the fortress from a very cold cave, there is no breath to be seen. (01:16:25)
Factual error: Quatermain sits in the snow for hours, without gloves, holding a rifle with substantial metal parts, yet his hands don't freeze onto it or (presumably) get frostbitten. (01:16:55)
Revealing mistake: In the scene where Allan Quatermain is waiting for Skinner in the snow and the white tiger shows up, when the camera shows a close-up of Allan, there is snow inside his goggles on his head. If it is snowing hard and the snow inside his goggles isn't adding up, it should have been melting or been melted. But it doesn't change at all, which proves it to be fake snow. How did it get in there anyway? (01:17:15)
Revealing mistake: When Skinner is walking around in the snow, after he says he's standing outside completely naked, he should have been leaving footprints in the snow. When he does, between shots, they're practically floating. (01:20:55)
Continuity mistake: When Gray stabs Mina and pulls the sword out of her body the blade is clean, only in close-up when he wipes it there are blood stains. (01:28:00)
Suggested correction: The stains are only at the top end of the blade. We don't see the blood because the part is embedded in her.
Continuity mistake: At the very end of the movie, Tom Sawyer works the lever action on his Winchester rifle before laying it on Quatermain's grave. On this type of firearm working the lever-action cocks the hammer, but a moment later we see a close up of the grave and the hammer is down. (01:41:40 - 01:42:30)
Continuity mistake: When the Phantom's men ambush the League at Dorian's residence Sawyer is seen joining them in revealing themselves and aiming at the League (you can tell it's Sawyer by his clothing and weapon). Then during the Phantoms speech Sawyer reveals himself again as if he was never there.
Revealing mistake: In the scene early on in the movie where Quatermain fights the goons in the bar, it is quite easy to notice when it is Sean Connery, and when it is his stunt double.
Audio problem: As soon as Nemo begins playing the record, we hear a woman say "Ready, professor?". However, the actual recording doesn't start until the needle is put into position, which is after she says that.
Plot hole: What on earth are those sailors doing with Hyde when he is chained up on The Nautilus? He is solidly chained to the floor and walls and they keep stepping up to him to allow him to swat them out of the way, risking injury or even death. They stand around like idiots as if waiting their turn to walk up to Hyde and be belted across the room. Why? Why are they even there? Hyde doesn't need subduing, and if he needed guarding they could do it without getting into range.
Suggested correction: They are there to subdue him because he is strong enough to tear the chains from the walls, which he does seconds after they stop trying.
Factual error: Apparently, Captain Nemo's submarine, Nautilus, is a shape-shifter. When it first surfaces next to the dock, it appears to rise easily 100 feet above the water, and that's only the visible part of the submarine; the bulk of the craft is still below the surface. This suggests that the water is a good 300 feet deep or more right off the dock, which is impossible. At this enormous size, it's also impossible that the Nautilus negotiates inland waterways, as when she goes to Mongolia. Strangely, we also see an overhead shot in which the Nautilus appears to rise only about 40 feet above the surface (compared to three-storey buildings directly adjacent).
Revealing mistake: In several scenes where Skinner is shown with his full outfit and makeup, you can see skin through the makeup. No skin should be noticeable on an invisible man. This is especially noticeable on his ears.
Deliberate mistake: After Mina leaves the car in Venice, Sawyer just manages to avoid several obstacles on the way, including a bend in the canal. But in the first scene, where Sawyer swerves the car around, its front should have slipped into the water anyway, considering the speed of the car and the tightness of the street, which makes a sharp L-turn at such close quarters next to impossible. But then the scene jump-cuts, and the car is well past the hazard.
Plot hole: As the Nautilus makes its way along a canal in Venice, you can see a bridge ahead of it that is far too low for the sub to pass under. Yet without altering its running depth, the sub miraculously appears in the canal well beyond this bridge moments later, and that bridge is not damaged.
Factual error: How did they get the Nautilus up the Thames? Or into Venice? They'd have had to dredge the river to get it into London. Also, what's really under Venice? I thought Venice was built on a marsh, why would there be all those nifty tunnels and columns under there, why not just foundations and such?
Other mistake: When Sawyer fires at the men on the roof in Venice, he shoots over 30 bullets from two six-shot revolvers.
