The evil criminal leader Kendrick has kidnapped an elderly biochemist who holds the secret to creating a biological superweapon. The only person who can possibly stop Kendrick and his gang is L. A. cop Sam Kettle and martial arts master Jun Kim (uncle of a little girl also kidnapped by Kendrick). Together, they go to war against an army of ninjas to rescue the hostages and bring their kidnappers to justice.

Tony, the new kid at school, befriends gang leader Young, whose top rival is Chan. When Young defeats Chan in battle, two mysterious men offer Tony and Young jobs at a security agency, with one of their new clients being among the city's most notorious drug dealers.