After the kung fu instructor of Chen (Lee) is brutally murdered, Chen seeks revenge. When he discovers that the killers are a Japanese gang, and that they are terrorizing his former school, Chen brings swift and deadly retribution to the evildoers.

Bruce Lee plays a martial arts student who returns to his former school to find that his beloved teacher has been murdered. Set in Shanghai in the 1930s, the Japanese are in control, and it is one of their Bushido schools that is responsible for this outrage. Knowing that the authorities will not attempt to bring justice to the killers, Lee seeks to restore honor to his institute and mentor with fearsome revenge.

There is an awkward romantic sub-plot and the script and direction can, at times, be a little crude, but the screen presence of Bruce Lee is undeniably strong. His fluidity in Kung Fu is amazing to watch, and he compresses the rage of a tormented culture into a physical art of retribution that promotes this film into a league of Asian classics.

In making this film, Lee tapped into a powerful sentiment that the normally undemonstrative Chinese audiences of the time stood up and applauded. The tag of Sick Man of Asia was used in the 30s by the Japanese Imperialist forces to describe the subjugated Chinese, and in this movie, Lee exacts a visceral vengeance of mesmerizing power.