Asia's Moody Hero.(Tony Leung Chiu-wai)

Tony Leung Chiu-wai is stuck in traffic. It is the height of the evening rush hour, and the Hong Kong actor is trying to reach the offices of Wong Kar-wai, who is directing him in the mysterious "2046," a film with no script. Leung won't receive his marching orders until he arrives at Wong's office: if the director says they're filming, the actors and crew will head for the latest secret location, where they might work until dawn. If not, they'll all just hang out. That is Wong's way, and Leung is used to it; "2046" is their fifth movie together. "Kar-wai is very demanding, and we never have a real script," says Leung. "[But he] challenges me. He is always pushing me to go deeper, to become that person. I like it."

Moviegoers and critics like it, too. The expressive but unassuming actor is winning worldwide notice with strong, quietly emotional performances, like his turn as a tormented pimp in "Cyclo." With the last film he and Wong made together, the 2000 art-house hit "In the Mood for Love," Leung took the best-actor prize at Cannes for his measured portrayal of a Chinese newspaper editor who discovers his wife's infidelity. If Wong completes "2046" by the April deadline, it is expected to be a contender at Cannes this year--and to feature another memorable performance by Leung.

The 40-year-old actor works well with other directors, too. In Zhang Yimou's latest epic "Hero," which has been nominated for a best- foreign-film Oscar this year, Leung plays a determined Qin-dynasty assassin. And he humanized the role of a psychologically damaged undercover agent in Andrew Lau Wai-keung's cop thriller "Infernal Affairs," which was Hong Kong's top-grossing film in 2002. "In Chinese films today, Tony Leung Chiu-wai is very important," says Hong Kong scriptwriter Alan Lee Kam-lun. "If it is a difficult, dramatic character, producers first think of him."

The actor's gravitas sets him apart from all the pretty boys, action heroes and slapstick comedians who dominate contemporary Chinese cinema. Indeed, Tony Leung Chiu-wai--not to be confused with Tony Leung Ka-fai, who starred in "The Lover"--may be the most serious actor of his generation. He has fan clubs all over Asia, and a devoted following among the foreign-film crowd in the West. "Leung Chiu-wai is No. 1 among Chinese actors," says ...