But let's return to that unusually balmy Sunday afternoon. The 46-year-old cuts in, mid-sentence, when I mention his nomination. "I hope wins at every category that it's competing in - except mine," he says, breaking into a grin.

His long-time collaborator and action auteur Dante Lam Chiu-yin bursts into laughter next to him. When I ask the director what he thinks about his leading man's chances, Cheung interjects: "We don't think about that stuff."

"But I do think about that," Lam says. "I've witnessed the immense amount of effort that he put into the role." Cheung underwent a dramatic physical transformation to look the part of a mixed martial arts fighter.

"It's not just about throwing yourself into a character - Cheung has gone beyond the ordinary level of filmmaking. I was there the whole time to witness his injury, the training after that, and his perseverance until the end," says Lam.

The effort has paid off handsomely for the actor. Before last Sunday's awards, Cheung had already beaten Tony Leung Chiu-wai to win best actor at last month's Hong Kong Film Critics Society annual ceremony. Cheung received another award at the Shanghai International Film Festival in June.

Cheung and Lam first worked together on the 2001 comedy , but it wasn't until they partnered for their run of three superior action dramas - (2008), (2010) and - that the duo won broad recognition.

Cheung was nominated for best actor at the Hong Kong Film Awards for each of those films, winning twice in the process - for and His memorable turn in the latter film as the ultimate underdog hero has further cemented his place at the centre of Hong Kong's pop culture zeitgeist.

"All the middle-aged men I've talked to told me that the film has given them a shot of confidence," Lam says. "I was talking the other day with [former Hong Kong Olympic cyclist] Hung Chung-yam. He told me that he had seen the film eight times in the cinema. And then he bought the disc and watched it at home five more times with his son."

"Oh my, that's insane," Cheung says.

In their latest film together, , Cheung is given a smaller - but no less meaty - role opposite Daniel Wu Yin-cho. Inspired by the real-life crime spree of rogue policeman Tsui Po-ko, Lam's story follows Wu's emotionally disturbed police officer as he strives to track down the leader of a gang of cold-blooded armed robbers concealed behind creepy masks. The gang's leader is played by Cheung with devilish relish.

Shot immediately after the upbeat was wrapped up, this relentlessly dark thriller is easily the 48-year-old filmmaker's bleakest effort to date. Indeed, much of was filmed on location at

coffin shops, cemeteries and funeral parlours to mirror the psychological horror experienced by the film's protagonists.

"When we were shooting the gunfights at the funeral venues, all the coffins on site were actually filled," Lam says. This revelation is much to Cheung's surprise.

"I'd been thinking about this story before I made It's because of that film that I intended to go the other extreme. This is what I set out to do from the start: I've made up my mind to take a trip through hell."

For Cheung, the mental switch from his overwhelmingly positive character in to the devil himself in was never a problem. "Our understanding of the creative process is automatic," he says. "Unless it's a special circumstance, like when I had to bulk up for , the rest is all on autopilot. As long as Lam is confident about his project, we can start right away."

The prospect of forming an acting-directing combo that lives on in the cineastes' imagination is one that Cheung merrily entertains. "I like this idea. I like it," he says. "I've actually talked to Lam about this before. I have a feeling that maybe he has projected some of his own qualities onto me. After all, we're a similar age, have very similar points of view on a lot of issues, and our interests match nicely.

"If you look around in Hong Kong cinema, Wong Kar-wai has his Leung Chiu-wai, Johnnie To Kei-fung has his Lau Ching-wan, and that's more or less it. I've always said that if you're to find a director standing next to Cheung Ka-fai, it is going to be Lam Chiu-yin."

When I ask if the pair have another collaboration in the works, the actor looks at me and puts the ball firmly into his partner's court. "I have no idea. I'm just waiting for my phone to ring."

Lam chuckles. "There will be, there most certainly will be," he says. "Actually, I've also given some thought to the issue you just raised. It's my ultimate wish that one day, when the collaborations between [Cheung] and me would stop giving the investors any qualms, we have the liberty to come up with any story we want.

"For instance, it could be a story like those in the Akira Kurosawa films, which focus on the daily life of one character and nothing more."

The director may have possibly been influenced by Cheung's confession that he wants to take part in "a quality biopic like " earlier in our conversation.

"We wouldn't need any cops or robbers or anything like that," Lam says. "I'd be showing this one person's life, in great detail and without reserve. That's my dream. I'd happily abandon all the knives and swords because I wouldn't need them any more.

"I look forward to that day."