In "My Lucky Stars", the two Hong-Kong cops are named Muscles and Ricky, played respectively by Jackie Chan and Yuen Biao. They travel to Tokyo to catch the ex-cop named Barbarian, played by Sammo Hung, who had stolen a large amount of diamonds. Meanwhile, a group of Japanese ninjas called the Flying Dragons is hired to protect Barbarian.
Muscles is captured by the Flying Dragons, leaving Ricky to reach out to his old gang, the Five Lucky Stars, for help. The Five Lucky Stars are a group of former orphans who grew up together in a Hong-Kong orphanage, and each has a unique skill set. They include:
- Kidstuff (played by Eric Tsang), who is a master of disguise and pretends to be a wealthy businessman to infiltrate Barbarian's hideout.
- Rawhide (played by Sibelle Hu), who is a tough-as-nails female cop who joins forces with the gang to take down Barbarian.
- Herb (played by Charlie Chin), who is a bumbling cook and provides some comic relief.
- Roundhead (played by Richard Ng), who is a cowardly but good-hearted member of the gang.
- and Smarty (played by Kiu Wai Miu), who is a suave ladies man and plays a key role in the gang's plan to take down Barbarian.
The Five Lucky Stars are initially reluctant to help Ricky, but eventually agree to assist him. They team up with Muscles and come up with a plan to infiltrate Barbarian's hideout and recover the stolen diamonds. The plan involves a lot of physical comedy, martial arts action, and car chases. In the end, the gang is successful in taking down Barbarian and the Flying Dragons, and the diamonds are recovered. The movie ends with the Five Lucky Stars returning to Hong-Kong and going back to their everyday lives, while Muscles and Ricky continue to work as cops.
