Bruce plays Chin Chin, a martial arts student in Shanghai, whose sifu is killed by a rival Japanese martial arts school. He decides to take it upon himself to exact retribution by soundly thrashing the whole of the Japanese school's students. When they retaliate the police step in. Chin Chin goes under cover to ferret out the guilty parties and kills the two spies who murdered his sifu. Now he is on the run with both the police and the Japanese after him. He carries on until all the guilty ones are dead, and then gives himself up. He dies by running and leaping at the cops waiting to take him in. Bruce's take on the end was that Chin Chin had to die since he committed murder, and could not go unpunished.
Of all of Bruce Lee's movies this one is perhaps the most realistic and enjoyable in terms of martial arts action even more so than Enter the Dragon. The plot of a country bumbkin sent away from his home that ends up singlehandedly humiliating and dispatching pestering gangsters is again implemented, but is this time seen entirely through Bruce's eyes as Bruce wrote this screenplay. Comedy punchlines that fall flat, plot somersaults that defy logic and reasoning leaving the audience discombobulated however are forgetable, but the choreography of the fights are the apex of on screen martial-arts action. The gladiator duel set in the Colloseum with Bruce and Chuck Norris is the most climactic scene, and I found myself rewinding the scene over and over to catch Bruce Lee's footwork that seemed comparable to Muhammed Ali's. The scene where Bruce Lee wields two nunchaka at once is asskickingly breathtaking.