Other mistake: Before Jack's car jumps over the bridge, a van skids on the road. The first angle shows a thug firing at Jack, and the second angle shows Jack swerving to the left to dodge the bullets. The editing is all wrong here: The thug fires at the opposite lane to where Jack is, so he is really driving to where the bullets are.
Last Action Hero (1993)
1 other mistake
Directed by: John McTiernan
Starring: Arnold Schwarzenegger, Ian McKellen, Charles Dance, F. Murray Abraham, Art Carney
Visible crew/equipment: When Jack first falls on to the elevator and is hanging on the side, you can see the reflection of the camera in the window. (01:15:45)
Jack Slater: Sir, are you a henchman?
Benedict: No, I only go as far as lackey.
Trivia: When they go into the police station, just before Robert Patrick walks out Sharon Stone walks out in her Basic Instinct outfit. Another nod to the "movie within a movie" concept.
More questions & answers from Last Action Hero
Chosen answer: The kid points them out in the film, in order to convince Arnold's character that he inhabits movieland. Also, after Arnold's character falls into the tar pit he is able to completely wipe himself clean, an obvious intentional continuity error.