Kos-Read, who is known in China only as Cao Cao, is by far the leading foreign actor working in the country today, having appeared in about 100 movies and television programs since his career began in 1999. He is famous throughout the mainland, and his career has been on a steady upward trajectory. Last December he appeared in the action film “Mojin — The Lost Legend,” currently the fifth-highest-grossing movie in Chinese history. ... just as Hollywood has begun to crack the market, Chinese cinema has come into its own. In recent years, Chinese studios have started shifting away from the agitprop that defined their cinematic output for generations and are instead focusing on genres that draw viewers to theaters in any country: action, adventure, comedy. In February, a sci-fi comedy called “The Mermaid” became the highest-grossing movie ever in China within 12 days of its release, earning more than $430 million. Increasingly, Chinese cinemagoers are opting to buy tickets for movies made specifically for them — like those in the “Ip Man” series — not those that pander to them or lecture them. It is in this sort of film that Kos-Read has finally had the chance to act, rather than portray a stand-in for Western imperiousness. If the Hollywood studios really want to understand how to succeed in China, Kos-Read’s journey makes for a kind of accidental guide.