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.

Mayoral candidate Dr. Rachel Larkin has a dangerous plan for swift justice in the form of a band of ex-convicts, called the Peacemakers, who roam the streets to do her bidding. When a boxer friend is killed by Larkin's thugs, an outlaw cop goes undercover to get evidence, and works his way up to the inner circle of the doctor's army.