Probable bans

Willy Lam, an expert on Chinese politics at the Chinese University of Hong Kong, told the Global Times, "There is no official censorship in Hong Kong and Taiwan, so writers and artists can pursue any topics as long as they do not break the law."

Even so, celebrities taking political stances risk losing the mainland market. Last November, Taiwanese singer Deserts Zhang displayed a Taiwanese flag during a concert at the University of Manchester. The issue flared up online, with netizens calling her action a declaration of Taiwan's independence. Following the incident, Zhang had to cancel a concert scheduled for that December in Beijing.

Other celebrities were banned from television shows following their political expressions. Annie Yi, an outspoken Taiwanese actress, was banned from a number of mainland television channels following remarks on Sina Weibo about press freedom last year.

When asked if he thinks these pro-Occupy Central celebrities will be officially banned from China's mainland, Bo Zhiyue, a senior research fellow at the East Asian Institute of the National University of Singapore, said, "I hope they won't be punished. This is a test for the government that they don't punish people for their political views."

Xi, the producer, said the SARFT's crackdown on tainted artists and the State media's ideological criticism of artists have been a reminder that companies should be cautious when they cast actors, so as to avoid potential risks.

"Some Taiwanese producers used to caution me about the political stands Giddens Ko takes. I didn't take them seriously. Now it seems like I was wrong," he said.

"Many production companies have signed agreements with actors, saying that if an actor has personal problems causing their work to be banned, he or she will have legal responsibility [for the losses incurred]," he said.