This is the first and only film in the American Ninja series to receive a PG-13 rating; the first four films received an R rating.
Who are you?
Hiro: You killed my father!
Viper: I kill many fathers.
About an hour and 15 minutes into the movie, the doctor is explaining how the nerve gas pill works. He has no glasses on. He turns and walks over to a device, still with no glasses. He stops, the camera cuts to another angle, and he has glasses on.
U.K. video version is cut by 1 minute and 11 seconds to remove all fight scenes featuring nunchakus and throwing stars, and to edit an ear clap and a scene where young Hiro is kicked in the head.