Revealing mistake: There is an obvious stunt double for Grandpa during the fight scenes.
3 Ninjas (1992)
Directed by: Jon Turteltaub
Starring: Victor Wong, Max Elliott Slade, Chad Power, Michael Treanor
Other mistake: When the three ninjas are kidnapped and locked in that room, Tum-Tum is complaining about being hungry. Later on, before the fighting match between Grandpa and Snider, Tum-Tum gives Grandpa jelly beans. Why didn't Tum-Tum just eat those before?
Continuity mistake: When Rocky and Colt go to the bathroom to attack Hammer after he drank the laxative, Colt thrusts a plunger to Hammer's face. As Colt thrusts it backwards, Hammer's face gets pulled forward, sending his ponytail over his head. In the next shot his hair is neat and tidy, not over his head.
Fester: Hey dude, what time does school get out?
Hammer: I don't know. I never stayed to the end.
Hammer: Dude.
