Revealing mistake: Mr Hyde makes no bubbles when growling underwater. (01:11:30)
Continuity mistake: When the members of the League are attacked at Dorian's home, the fight is accompanied throughout by a blizzard of paper falling from a height, yet hardly any of the books have been disturbed on their shelves. (00:28:40)
Continuity mistake: When the assassin takes Mina as hostage and holds a knife to her throat, Mina's scarf is under his arm. Two shots later the scarf is hanging over his hand. (00:27:50)
Factual error: In a shot near the beginning of the film, the gravestone for Allan Quatermain's son is misspelled "Quartermain". [People are trying to correct this, saying the spelling's correct - no it's not: http://uk.imdb.com/Title?0311429.] (00:12:50)
Continuity mistake: The invisible man is seen in one shot with cream covering the majority of the front of his face but it ends towards the middle of his head. When he is in the automobile, the cream is now completely covering his head and neck. Then, when they go to see Dorian Gray, only his face is covered with make-up again. (00:17:50 - 00:22:35)
Continuity mistake: When Mina tries to see what is the composition of the powder found on the deck, the amount of liquid in the test tube changes between shots. (00:47:55)
Continuity mistake: When Quatermain arrives in London, he is greeted by Reed who leads him down some stairs. In the shot where they're going down some spiral stairs, for some reason you see a different actor (who is clean shaven) posing as Reed, going down the stairs holding the umbrella in his right hand. Then in the next shot you see the "original" actor who has a slight goatee and is holding the umbrella in his left hand. (00:13:25)
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)
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)
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: 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.
Continuity mistake: When Reed's cart stops in front of the Kenyan club there's no other cart around, but when the camera angle changes there's another one passing by. There's also a huge basket on the side of the road which hasn't been there before. (00:05:20)
Factual error: In the first few scenes they show some newspapers. They show Tuesday April 10, 1899, then Thursday May 18th,1899. If April 10th is on a Tuesday, then May 18th can't be on a Thursday, it would be on a Friday. April 10, 1899 was actually a Monday, but May 18th that year was indeed a Thursday. (00:03:45 - 00:04:55)
Factual error: When the League arrives in Venice, Carnivale is being celebrated. In the film they leave London in July and arrive there a few days later, but in Venice, Carnivale is celebrated on the last weekend before Lent - which differs from year to year, roughly between early February and early March. (00:13:15 - 00:53:05)
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 the building explodes in the beginning, the man sent to recruit Quatermain walks close to him. When it cuts the man is a few feet away from Quatermain. (00:11:45)
Continuity mistake: Mina's hair turns curly whenever she is in vampire mode EXCEPT when she is in Dorian's library and attacking the goon who held a knife to her throat. (00:29:20)
Suggested correction: Because she doesn't go "Vampire mode." She simply sucks his blood.
She's can't suck his blood without turning into a vampire. Her "vampire mode" includes having fangs used for sucking blood.
She is able to control her transformation. She's progeny of Dracula himself. She's extremely powerful.
Factual error: In Venice, Quatermain hunts down M in a cemetery, only there is no cemetery in Venice. The burial ground is on the island of San Michele in the lagoon. (01:01:25)
Visible crew/equipment: When Hyde is first brought aboard the Nautilus, he is loosely chained, but still tossing crewmen about. There is one crewman, whose back is toward the audience, whose striped shirt puckers around the harness as he is jerked backwards. (00:36:00)
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.