Scott James, a veteran martial arts expert, is recruited as the protector of the wealthy and beautiful Justine after she becomes the target of a ninja clan. When Scott finds out that his ruthless arch-nemesis, McCarn , is involved with the stealthy and dangerous criminals, he is eager to settle old scores. Soon Scott is facing off against McCarn and the entire ninja horde in an effort to take them all down.

In the Edo period, at the remote village of Okitsu, the evil cult leader Koushirou uses ninjutsu to bewitch sharks and forces them to attack local pearl divers so the cult can steal the pearls from their mangled corpses. Desperate for help, the village chief hires Kotaro Shiozaki, a guard at a nearby temple, but Kotaro soon finds his path blocked by lady ninja Kikuma and a gigantic shark that doesn't seem like something from this world.