Ah Chau (Richard Ng) and Beethoven (John Shum) are a pair of cops investigating a drug lord, but their ineptitude threatens to derail the case. The police are well aware that Mr Sha (Chan Lung) is the boss of the crime syndicate smuggling and trafficking in drugs, and that he keeps details of his criminal transactions in a book which is kept by his mistress. When Beethoven and Ah Chau investigate, they find Sha's mistress dead, and inadvertently compromise all fingerprint evidence in the hideout. Luckily, they are assisted by beautiful cop Inspector Anna (Deannie Yip), who is secretly attracted to Ah Chau. Finally the two make their arrests and become instant heroes.

Cast and roles[edit]

• Richard Ng - Ah Chau (sometimes listed Achioo) as / Walker / Ng Ah Chiu
• John Shum - Beethoven / Johnny
• Deannie Yip - Anna
• Philip Chan - Inspector C.K. Chan
• Tai Po - Pimp Chou Wen
• Chung Fat - Columbo
• James Tien - Chief Inspector Tien
• Peter Chan - Mr. Sha
• Wu Ma - Police Station Employee / Painter
• Dennis Chan - Police Station Employee / Painter
• Kan Ng Min - Keung
• Kit Lee Chi - Pui
• Dick Wei - Scarman
• Yuen Biao - Garbage Truck Driver
• Sammo Hung - Eric / Kidstuff / Chi Koo Choi (Cameo appearance)
• Stanley Fung - Rawhide (Cameo appearance)
• Charlie Chin - Herb (Cameo appearance)
• Mars - Motorcycle Cop #1
• Jackie Chan - Motorcycle Cop #2 / Skater
• Lam Ching-ying - Police Sergeant
• Lau Chau Sang - Mr. Sha's Thug
• Johnny Cheung - Mr. Sha's Thug
• Steve Mak - Mr. Sha's Thug
• Chin Kar-lok - Mr. Sha's Thug
• Pang Yun-Cheung - Mr. Sha's Thug
• Wellson Chin - Police Station Employee
• Chin Yuet Sang - Passenger in stalled car
• Chong Man Ching - Driver of stalled car
• Fung Ging Man - Mahjong player
• Tai San - Bill