Continuity mistake: When Gillian escapes from the facility, Hester runs out the door after her and collides with the guard coming from the opposite direction. For a second, they rebound in opposite directions, then it cuts and she falls on top of him (the same direction).
Continuity mistake: When Jake and Link are watching TV Jake is lying on top of the settee. Link says hi to Jake and the camera switches from Link to Frank. In the next shot Frank sits down and Jake is gone. He had no time to move.
Continuity mistake: Near the end of the film, when Richard Gere and Brooke Adams is by a boat and attempt to escape up the river, Gere is shown waving a kerosene "barn lantern" to illuminate the boat. In a slightly later shot, he is doing the same thing, but the lantern has become a Coleman gasoline lantern. These lanterns had not been invented yet in 1917, the year during which the scene in question takes place.
Revealing mistake: During the fight after Witty has been killed, Peiter throws a grenade that lands in a bush on the right of the path up which the enemy are advancing. However, the resulting explosion comes from the centre of the path and not as far away as the grenade flew.
Visible crew/equipment: When Dr. Wheeler is leaving the Jefferson Institute after talking with the nurse, you can see someone reflected in the glass door holding a book or some papers.
Visible crew/equipment: When Gene is on top of the coaster at the amusement park, you can see a cameraman below filming.
Character mistake: In the scene where the Panthers are being introduced, the announcer states that one boy is "Walter 'The Hook' Coster", and another is "Frank 'The Razor' Schmidt". But in another scene, when one of them is batting, he says Frank Coster. Although they look exactly the same, he accidentally mixed the two names together. There is no Frank Coster. (01:12:50 - 01:19:15)
Revealing mistake: While Billy and Eli are on the river, with Eli in the front and Billy in the background, pay attention to Eli's paddle. When it passes in front of Billy, you can see right through it to see Billy through the paddle. (00:56:25)
Revealing mistake: In the opening scene, the tomato in the sink starts moving and as it comes up toward the rim, you can see a person's finger as they toss the tomato in, revealing the whole thing is run in reverse.
Continuity mistake: In the first film, "National Velvet," the Pie, Velvet Brown's horse that ran in the Grand National, was a gelding (neutered). In the sequel, the Pie has somehow become a stallion again and sires a colt many years later that Velvet's niece names Arizona Pie.
Continuity mistake: When Tony and Tia are being driven to their hotel, the same footage is shown behind them a few times e.g. A truck turning off the road when their driver shouts at an overtaking driver and a few minutes later when he shouts at the same driver again.
Revealing mistake: When the neo-nazis burst into Kohler's apartment, they stab him and he slides down with his back against the wall. While Mengele picks up the phone, you can see the 'dead' Kohler blink in the background.
Continuity mistake: Though Fausto Zoppi and Jean-Claude Moleno are to have contributed to the 'World's Most Fabulous Meal' for the Queen, neither of them ever shows up in the kitchen during the preparation of the dinner. They don't even appear until much later in the film.
Continuity mistake: Towards the end of the movie, after FVB (Aerosmith) sings, and Strawberry Fields (Sandy Farina) falls off of the platform. She lands on her front, but when Billy Shears (Peter Frampton) runs down the stairs to her, she is on her back.
Factual error: At the end of the fight between Pai Chang Tien (the Old Man) and Shu Chin (the fan-wielder), Pai catches his opponent with his pipe on the larynx and strangles him to death. In his death-throes Shu Chin groans until he dies; but with a piece of wood pressing down on his windpipe, he realistically wouldn't be able to make such a pronounced sound. (01:19:10)
Continuity mistake: When Fiona and Paul first go inside the castle and rescue the professor from his time machine, they are standing talking to the prof. Fiona is on the left and Paul is on the right. The angle changes, and Paul and Fiona have swapped places. Another angle change, and Fiona and Paul are back in their original positions.
Continuity mistake: When Jeff gets into the studio, the album playing is in the middle of the album, not at the end as shown one minute earlier. (00:05:26)
Factual error: In the sixties retro scenes vehicles can be seen that didn't start production until the seventies.
Visible crew/equipment: When Travis and Jessie investigate what was reflecting sunlight, a Kodiak Bear attacks. When Jessie climbs a tree to get away from the bear, you can see a hand reaching down to help him get out of harm's way. (01:15:00 - 01:16:00)
Factual error: In the closing scene, E.J. Bellocq pictures Hattie and Violet with a Kodak Portrait Brownie No. 2. The Kodak Portrait Brownie No. 2 was not introduced until 1929, a dozen years after the movie takes place.