Where the Wind Blows is a crime thriller covering many decades of police corruption on the Hong Kong Island and Kowloon/New Territories at a time when both areas were still under British colonial rule.
The original title was going to be Theory of Ambitions, given that the film tells the story of two policemen who want to leave their thankless low-class existence behind by cooperating, and later dominating, the local triads (Chinese gangs, comparable to the Yakuza in Japan). They find success. And acquire enormous wealth and influence.
According to director Phillip Yung, the film stays very close to the actual historical events. Starting in the 1940s, with bomb raids and the occupation of Hong Kong by Japanese forces, the narrative follows two police officers: Lui Lok (Aaron Kwok) and Nam Kong (Tony Leung Chiu-wai). We get to see how they are recruited and start their careers in law enforcement.
We learn that Lui joined the police academy with clear idealistic motives. He wants to serve justice. He refuses bribes from street vendors and is promptly beaten up by his colleagues for such an unacceptable attitude. They accuse him “to be a snob” since bribery is “as normal as getting up in the morning and brushing your teeth”.
He is left with no choice. Once it is obvious that he cannot escape petty corruption, he decides to go for corruption on a grand scale. 
Nam is his partner in crime, a well-groomed gentleman who moves effortlessly within the police force, the high society, and the criminal underworld.
Both men’s abilities to secretly work with the triads make them look like heroic crime fighters. Both become legends. Nam is even promoted to Chinese Chief Detective, in 1962. The power plays orchestrated by the two men for many decades make the film truly epic. And so was its genesis.
After years of intense preparations, the actual shooting started in 2017. A global release date was set for the later months of 2018. But that did not happen. All of a sudden, the National Radio and Television Administration informed the film’s producers that Hong Kong’s authorities were uncomfortable with a film plot depicting a shameful phase in Hong Kong’s history.
A change of mind came in 2020. Eventually, the film was scheduled to open in April of 2021. But, three days before the world premiere at the 45th^th Hong Kong Film Festival, it got taken off the official list.
Later that year, Where the Wind Blows finally had its national premiere, qualifying for Golden Globe consideration and as Hong Kong’s official representative at the Oscars.