Organized crime's ""Protection"" Boss Duke Slate decides it's time to acquire the oriental businesses in town and uses Low Sing's gang to handle his influence. Low Sing, a martial arts professional, instructs his craft to his gang using the actions of a caged Preying Mantis, analogizing its intricate moves to proper Kung-Fu application. After a kidnapping, engineered by Low Sing, a challenge between Low Sing & Kato results in an interesting result.