HONG KONG - To hear Hong Kong director Dante Lam tell it, filming the fight scenes in his new movie Unbeatable was like playing a computer game.
"I got more and more excited watching the playback on the screen.
When filming began, I sat there and said, 'Hit harder, hit more, change position, hit there.' But obviously, the two actors were really feeling a lot of pain doing all of this," he says.
"Working with me is really not easy. I ask for a lot."
And yet the male leads in the movie gave him all he asked for and more.
That is why Lam feels he struck gold with the casting of Nick Cheung and Eddie Peng as boxers in Unbeatable, which is showing in cinemas.
Cheung plays a boxing instructor at a gym who trains Peng for a mixed martial arts championship.
Few other actors would have been as willing to undergo such torturous physical training as these two for their roles, says the film-maker.
Speaking to Life! over the telephone from Hong Kong, the 48-year-old director adds in Cantonese: "The movie's budget was not very big, the filming hours were long and working conditions were tough.
Training for the roles alone was very demanding because the actors needed to transform their bodies to look like real mixed martial arts fighters.
"Not many actors would have been as willing as Nick and Eddie to go through these training requirements."
Indeed the two actors went through hellish fitness and diet regimens.
For nine months, Hong Kong veteran Cheung hit the gym for at least three hours each day and lived on a diet of egg white, boiled chicken and steamed fish.
Taiwanese heart-throb Peng, already looking rather muscular from his training for his gymnast role in Jump Ashin! (2011), had to intensify his regular training routine until his body fat went down to just 3 per cent.
Lam says he cast Peng, 31, because he knew the star is able to challenge himself physically.
"I heard he took a whole year just to train to look like his character for Jump Ashin!. Can you believe that? A whole year. Where can we find young actors like that these days?
"So I had a good feeling that if he was interested in the role in Unbeatable, he would be willing to push himself even harder physically.
And I was right.
When Eddie puts his mind to it, he really gives his all.
He has great potential in this industry." Cheung is perhaps even more impressive, given that he did the same thing as Peng but at the age of 45.
No wonder Lam sings his praises: "Nick is a big star but he is willing to do this because he's always looking to challenge himself.
Whenever I talk to him, he always says that he wants to try something new.
So when he agreed to do this, I knew that he really meant it.
After working with him for so many years, we're on the same wavelength and I know what he's thinking."
Unbeatable is the fourth film collaboration between the actor and director.
For their 2008 action-thriller The Beast Stalker, both men were winners at the Hong Kong Film Awards: Lam received the award for Best Director while Cheung won for Best Actor.
Lam says: "There is an immense sense of trust between Nick and me. We don't need to break everything down to understand what the other person is thinking.
"Trust between an actor and a director is so important.
It gives the actor the sense of security to go all out for the role and take it in the direction he wants, rather than worry about whether the director will be okay with it.
That's why I keep casting Nick in my movies, because we have that trust."
Anyone who has watched Lam's older films such as The Viral Factor (2011) and Sniper (2008) will think the film-maker is obsessed with big guns, cops and loud explosions.
But in Unbeatable the action takes a backseat to the characters and drama around the boxing ring. It is a clear departure from his oeuvre, albeit a temporary one, he says.
"I love a good action movie and I will keep doing major action films, but I felt like I needed to do something different. There aren't many boxing movies in Hong Kong, so I thought this would be fresh and different from the usual cop movies. If many film-makers start making boxing movies, then I can go back to making big action and cop movies," he says with a chuckle.
In fact, he had thought of making a movie about mixed martial arts five years ago and was just waiting for the right actors to come along.
"At that time, I just felt like I didn't have the right actors.
Nick has proven to me time and again that he has what it takes to push himself, but he had other things to do when I first came up with this movie concept.
"As for Eddie, a young actor like him is really rare. Even though he is getting more popular, he still puts in all his effort. I am really very lucky to have gotten both of them."
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