世仇 忍者錠 (1981)

International agents have failed to track down the high-level source of government top-security leaks. Japanese officials suspect the involvement of a group of cold-blooded Ninja Warriors, the fierce, EGA clan . But they are powerless against this tight, efficient killing machine. Desperately, the police seek the help of the one man who can destroy the Ninjutsa murderers and restore the governmental secrets. Ken Sacaki, the last descendant of the Koga leaders and a Ninjutsu champion himself, must accept the ultimate challenge against his bitter rivals. It's all up to Ken to defeat his oldest enemies and avenge his ancestors... or die trying. Hong Kong, Japanese and US co production.