In 2012, Knowles got his first role in the Chinese TV series Big Sister's Store.

It was also the same year that China overtook Japan to become the world's second-largest movie market, which grew at an average rate of over 30 percent year on year until 2016.

"Those were the best years. I was lucky to enter the industry at that time," he says.

Meanwhile, Knowles was admitted by the Beijing Film Academy, a cradle for most Chinese stars, as the first non-Asian student to be granted a full Chinese government scholarship in 2013.

After graduating from the one-year program, Knowles found his path to stardom becoming smoother.

"Most actors or actresses I met on the sets were graduates from the academy. I call them 'shi ge' (senior alumnus) or 'shi jie' (older alumna)," says Knowles.

Knowles, who has been featured in more than 10 Chinese TV series and movies, is now one of the best-known Caucasian faces based in China.

His works include the Nobel-winning Mo Yan's television adaptation of Red Sorghum, the biographical series Deng Xiaoping at History's Crossroads, and the hit romance thriller series Love Me If You Dare.

For most China-based foreign actors, a common problem is that they get stereotyped.

Asked if he faced the problem, he says: "I think China is moving away from this model. As storytelling skills develop, the (foreign) characters are becoming more interesting and complex."

Speaking of Asura, he says he does not look very different from the Chinese actors in the film. He says the main reason that the director picked him is his strong physique.

Knowles, who trained for three months, including practicing stunts for the movie, says: "People were 'flying' between mountains using wires. I've never been in such a big action movie."

Knowles, who now divides his time between Los Angeles and Beijing, sees a bright future for himself on the mainland.

On Dec 28, the day he concluded filming for Asura, he wrote on his WeChat account: "Goodbye China, I will definitely come back."