Kong became involved in Firestorm because he was attracted to the story about a senior policeman's struggle with career and friendship.

While some feel that audiences are tired of gang thriller-type stories, Kong believes in it.

"For me, genre is never a decisive factor in a film's success," he says. "What the audience wants is good content. The best gang thriller is yet to come, there is always the next one."

Lau believes the 3-D approach will be a highlight.

"The director impressed me by his understanding of film technology," he says.

"Few scriptwriters, as far as I know, are so good at computer graphics and 3-D. In this film, I began to realize 3-D could enhance not only actions, but also emotional scenes."

In a trailer released on Sept 23, Lau held a machine gun when running on the streets of Central district, the most busy business compound of Hong Kong. The area allows filming only from 8 to 11 am on Saturday and Sunday.

"If we followed the rule, we would have finished the film when I am 54 years old," Lau says.

So he convinced Kong to spend HK$15 million, to build a life-size set of the district - half of which comes from his pay as an actor.

"I read every script sent to me and revise it again and again, but I would only be fussy before the filming starts. Once the filming starts, I give the director full respect and support," Lau says.

In one scene Lau jumped from a skyscraper, and he claims he did it himself.

"No stuntman would do that for me, they all go to mock shows to imitate me, that makes more money," he jokes.

It has been Lau's dream to direct a film himself.

"I have seen many young directors, very talented ones," he says.

"They know today's audience better than I do. I would love to help them.

"If I decide to direct a film, it must be something very special. Otherwise I would rather not do it."

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