Lu's latest outing is one of his most audacious roles yet. Not every actor would consent to locking lips with another man on screen - but that's what Lu does in Hong Kong indie director Kit Hung Wing-kit's Soundless Wind Chime, in which he plays a Beijing-born delivery boy, Ricky, whose passionate relationship with a rebellious Swiss expat named Pascal (played by Bernhard Bulling) is cut short when the latter dies in an accident.

Distressed, Ricky travels to Switzerland to mourn his lover, only to meet Ueli (also played by Bulling), who looks identical to Pascal but has a vastly different personality.

'I love challenging myself with roles that have true personal traits, characters who are of the quiet and intellectual type. You don't come across interesting characters very often,' he says. 'I immersed myself into the life of the character I played and I went deeper as the filming went on, to a point that I believed I was really him. When I finished filming, I was amazed by the new side of myself that I'd just unveiled.'

Just like Ricky - who lives in Hong Kong in the story - Lu also left home when he was young, moving to Beijing in 2000 to enrol in the Central Academy of Drama. Lu says he empathises with the dislocation that Ricky feels.

'I also felt confused and insecure when I was alone in Beijing,' he says. 'I didn't know where my future was. I just wanted to get away from my mundane life and hoped a change of environment could make my life change as well.'

And change he did - he originally studied screenwriting, but found himself veering towards acting when he landed a role in Peacock after impressing Gu at an audition.

'I went to the audition out of curiosity and a bit of peer pressure because all my dormitory mates were going as well,' he says. 'I never intended to become an actor - it just happened.'

Playing the timid, sensitive youngest child of a working-class family in 1970s China (with Zhang Jingchu and Feng Li playing his siblings), Lu fell in love with acting, thanks to the pleasant experience he had on set.

'If Peacock hadn't been the first film I starred in, I probably wouldn't have continued acting,' says Lu (right). The film won the Berlin International Film Festival's runner-up award, the Jury Grand Prix, in 2005. 'Everyone in our team was so nice to me; they encouraged me and inspired me. They showed me how wonderful it was to make films.'

After spending four months making Peacock, Lu went back to the academy, but returned to the screen the following year in Courthouse on Horseback, in which he played a young judge who is sent to work in a rural village in Yunnan province.

A string of appearances in independent films followed, including Dutch filmmaker David Verbeek's urban drama City of Trance and Korean-born Swedish screenwriter anddirector Oscar Petersson's No Matter What.

Despite his impressive r?sum?, Lu remains modest about his abilities. 'I don't think I'm a very good actor yet,' he says. 'I want to experience more in life and become more mature.'

Still based in Beijing, he says he plans to continue writing screenplays and act. 'For me, screenwriting and acting are the same thing - both are about expressing myself. It's just the way of communicating that's different,' he says.

His self-effacing demeanour, however, belies an ardent ambition to create stories that will be 'life-changing'. 'I want to make films that can spread the seeds of hope to people all around the world, even to people in the far future,' he says.

Soundless Wind Chime opens Jul 23