Deliberate mistake: There is a huge security breach in the scene with Robin Williams and Christopher Walkin walking at night. The Security SUV limousine is more than 30 metres away from them. It should be pacing them in case of an emergency and be right next to them on the sidewalk. It appears the reason it is so far back is because at the camera angle the scene is shot at, it makes for a good background element which you would not see if the Secret Service followed protocol.
Deliberate mistake: When Hellboy is attacked by the spider-lady, as the spiders begin to descend on him to steal the sword, you can easily tell that some of the shots of the spiders coming down are repeated 2 or even 3 times, and simply flopped horizontally to appear different.
Continuity mistake: When Chris is hit by a car, he has both shoes on after the impact, when he is rolling on the ground. One of them suddenly disappears in the following shot.
Continuity mistake: In the scene where Thor hits Hulk with his hammer, he swings it, but in the next shot it shows him with his arm extended as if he hit him with his fist. (01:01:45)
Revealing mistake: When Gabriel Noone goes to see "Peter", he arrives in rural Wisconsin, looks out of the window of his car, and sees a mountain in the distance. There are no mountains in Wisconsin.
Plot hole: Spoiler Alert: Bruno gets through to the 1 million Euro question on the French version of "Who Wants To Be a Millionaire" (WWTBAM) and gets stuck on a question. He decides to call Francois as his Phone-A-Friend. However, Francois is sitting at home watching the drama unfold on TV. The basic premise of WWTBAM is that it is recorded to ensure that a friend who is called could *not* simply use the internet to research a response.
Factual error: In this Sci-Fi Channel TV movie, a geology professor and his students are climbing the side of an Icelandic volcano. The professor tells them, "There's a book by Jules Verne: Voyage to the Center of the Earth." He may not be an English prof, but he should still know better. Verne's book is Journey to the Center of the Earth.
Visible crew/equipment: When Olivia follows Mike into a restaurant, visible behind her is a Grip/Gaffer Flag on a stand blocking light in front of the window. The flag is noticeable in two shots and disappears in one.
Revealing mistake: In the scene where Rooster is driving/running away from the gangsters, he is supposed to be alone in his car but in one shot a hand appears and is holding on to the passenger side door from inside the car.
Visible crew/equipment: When the girl is bleeding to death in the bathroom you can see a reflection of a camera in the sinks and cabinets.
Continuity mistake: Arthur had only 36 hours to spend in the Minimoy world, and he leaves at midnight. He spends a full 24 hours too long as a Minimoy. After he finds the Minimoy Princess they travel during the day. They spend the first night sleeping in a flower (24 hour mark); the second night he is wandering under the house, the grandma is sleeping in a chair above him (48 hour mark). He then returns at noon. That's 60 hours.
Continuity mistake: In the scene at the Christmas party Mr Warne tops up the coffee cup with brandy to give to Miss Wiggins. At this point the cup is full to the brim but when he then carries a tray with this cup on it looks barely full.
Continuity mistake: When Ted is using the kite to steer the balloons, he is holding the string in his hand. When George's balloons pop, Ted catches George, and both of Ted's hands are seen to remain empty for at least 15 seconds, no kite or string is seen at all. Then it immediately cuts to a wide shot after George climbs onto Ted's back, and Ted is suddenly holding the kite string, and we see him continue to use the kite to steer the balloons. Ted did not have time to tie the kite string anywhere else, as he had it in his hand as he reached for George.
Continuity mistake: When Natalie gives Sara's diary to Adam, there is a close-up of the book in Adam's lap. Natalie is holding the diary with both hands, then she removes the top hand and moves the bottom hand to Adam's knee where it also rests on one of his hands. In the long shot immediately thereafter, Natalie's hands are clasped in her own lap.
Continuity mistake: When the little girl goes to the lunch wagon you see a bottle of apple juice behind her shoulder. When she walks away the bottle has been slightly turned and see can see more of the label.
Revealing mistake: In the scene where Shen is seen walking down the road as he tries to hitch a lift, you can see all the cars are driving on the right side of the road. However, in some background shots you can see the traffic moving on the left side of the road as it is supposed to in New Zealand where the film is shot.
Continuity mistake: When they're travelling in the coach, wideshots of them driving show them driving through deserted countryside. But in shots from inside the coach you can see the roofs of houses and telephone poles passing by.
Continuity mistake: When Ernie lifts the bike, he picks it up by the top wheel. When he is shown carrying the bike a second later, he is holding it by the lower bar.
Continuity mistake: When the hole is being punched in the ceiling and gets larger and larger, one shot reverts to when it was barely started.
Continuity mistake: In the scene where Dean Cain's character and the girl are chained together with the shackles. Dean leaps through the window and crashes to the floor. The girl then jumps through the window and neither of them is wearing shackles. There was no cut, and no indication they had a key.