
Long Arm of the Law (省港旗兵, "Guangdong and Hong Kong Criminals") is a 1984 Hong Kong film directed by Johnny Mak. The film was followed by two sequels: Long Arm of the Law II (1987) and Long Arm of the Law III (1989).

A group of desperate Chinese criminals hope to make a quick, effortless score in Hong Kong. Things go afoul, and the gang must hide out until the heat dies down, besmirched with the blood of an undercover cop.

The Royal Hong Kong Police put into operation a new plan to counteract the problem of increasing violent crimes committed by new arrivals from across the border in China. In agreement with Chinese authorities, three Hong Kong detectives go undercover as illegal immigrants in order to infiltrate the powerful gang that is organising the crime wave.

An ex-soldier/escaped death row prisoner flees to Hong Kong and is forced to work for a gang of criminals when they kidnap the woman he loves.

A group of Hong Kong criminals are hired to rescue student protesters fleeing mainland China. Caught in a political tug-of-war, they must evade ruthless mainland authorities pursuing them at every turn.