Joe Armstrong, an orphaned drifter with little respect for much other than martial arts, finds himself on an American Army base in The Philippines after a judge gives him a choice of enlistment or prison. On one of his first missions driving a convoy, his platoon is attacked by a group of rebels who try to steal the weapons the platoon is transporting and kidnap the base colonel's daughter.

On a remote Caribbean island, Army Ranger Joe Armstrong saves an old friend from the clutches of "The Lion", an evil super-criminal who has kidnapped a local scientist and mass-produced an army of mutant Ninja warriors.

Jackson is back, and now he has a new partner, karate champion Sean, as they must face a deadly terrorist known as "The Cobra", who has infected Sean with a virus. Sean and Jackson have no choice but to fight the Cobra and his bands of ninjas.

The two American Ninjas, Joe Armstrong and Sean Davidson, team up to do battle against a terrorist and his band of Ninjas.

When a scientists daughter is kidnapped, American Ninja, attempts to find her, but this time he teams up with a youngster he has trained in the ways of the ninja.