Revealing mistake: During the sequence with the Native Americans chasing the Delorean in the beginning, in one shot looking up at the sky you can see contrails from a plane, obviously not around in 1885. (00:19:25)
Continuity mistake: When Doug is running from the bad guys after finding out what was going on from his "wife", he tucks his big gun in to his jacket pocket. When he is running through the scanner, that big gun is now in his pants. (00:28:15)
Visible crew/equipment: Near the beginning of the film when the police car explodes and flips over, you can blatantly see stunt wires used to aid in flipping the car. (00:02:45)
Continuity mistake: When McLeach is using Cody to fish for crocodiles, the hook fastened to the rope around Cody's waist can be seen facing different directions in various shots. (01:06:45 - 01:09:35)
Visible crew/equipment: When the Red October sub has surfaced to let the crew get off because of the supposed nuclear leak, there is a brief shot where you can clearly see the camera and its filming crew in their tennis shoes on the deck. (01:45:52)
Continuity mistake: The telephone on Scrooge's desk briefly disappears after his maid delivers an invitation to the archaeological society ball. (00:19:05)
Continuity mistake: Marianne Graves gets out of the limo at the beginning of the movie; the smoke in the chimney goes from left to right between shots. (00:02:50)