The Hong Kong way

As a Hong Kong native, Lau had little knowledge of socioeconomic conditions on the mainland in the 1980s, but that did not bother him.

"What we are talking about is human nature, and that is shared by all human beings in different places through different ages," he said.

Lau approached Caught in Time, which is yet to be released, as a costume drama.

He consulted mainland police officers who started their careers in 1980s, asking them to share their experiences. He also turned to other writers and scholars.

Lau feels it is essential to understand how people think through the challenges they face, and this is his formula for telling a good story.

Throughout the filming, he could feel his characters grow. Lau met with his production team and the actors to come up with new twists to the original plot. It was "very Hong Kong-style", he said.

Lau learned his craft from mentors such as director Johnnie To Keifung, screenwriters Yau Nai-hoi and Felix Chong Man-keung - all big names who have created classic Hong Kong crime films since the 1990s, such as The Mission and Infernal Affairs.

Lau described his method of filmmaking as "using the Hong Kong way to tell a story on the mainland".

He moved to Beijing in 2007, where he signed on to write films such as Three Kingdoms: Resurrection of the Dragon and Painted Skin. Last year, he spent six months in Jiangmen, Guangdong province, producing Caught in Time.

Lau has made the mainland his place of work, like many Hong Kong filmmakers.

Fung Wing, general secretary of the Hong Kong Film Development Council, said most Hong Kong filmmakers have a basic understanding of Chinese history, culture and society.

"As long as they find stories that make them feel connected, they can make good films," he said.

He cited Operation Red Sea, based on the 2015 mission to rescue Chinese citizens in Yemen, as an example, saying that Dante Lam was the perfect choice of director because of his rich experience in helming war and action films in Hong Kong.

In recent years, more Hong Kong filmmakers such as Lam and Lau, who have mastered skills in storytelling and project management, have presented good films with Chinese cultural and political backgrounds, such as Operation Red Sea and Caught in Time.

Fung said this is a win-win situation for the industry. Hong Kong filmmakers can control the quality of such films, and at the same time access more resources and higher budgets to make movies.