F/X2 (1991) - 6 mistakes

Revealing: When Rollie is hanging from the ladder and the bolt breaks, you can see the smoke from the exploding bolt.

Visible crew/equipment: At the beginning when the robot is shot at, it goes to scratch its head but it is so obviously someone else's hand and arm doing the scratching as you can see the robot's arm at the same time.

Continuity: Ray Silak introduces Leo McCarthy as, "NYPD retired. He's a private eye, now". Leo was not retired, he was suspended (i.e. fired) in the first movie.

Factual error: Take a look at the directory listing on Chris' computer. It is absolutely absurd. The game Battlechess, for instance, is shown having the filename BATTLECH.ESS . No popular program uses an .ESS extension. It should be BATTLE.EXE . Besides, Battlechess takes a whole CD by itself. It would not be on a single floppy with a bunch of unrelated files.

Continuity: Towards the end of the movie, when the mob appraiser has verified the medallions are authentic, he is wearing two white gloves. He then asks if he can leave. When he stands up and gathers his things, he has only one glove on. The shot cuts away. When it cuts back to him, he has two gloves on again.

Deliberate "mistake": Smoke from a smoke machine smells very acrid, is standard temperature and would never be confused with hot steam from a shower. The man with the knife would have suspected something is wrong once he was in range to smell and feel the "steam".