Leung moved to the United States and, in 1974, opened a martial arts club in New York. As his reputation grew, Leung was invited to teach elite operatives within the US law enforcement and military community, including FBI agents and US Navy SEALs. In recent years, however, the 77-year-old master retired and returned to China.

In the summer, Leung suggested to Freitas that he should visit He Liangxing, a former fellow apprentice, in Shunde district in Foshan.

"For me, the main reason that I chose to practice Chinese kung fu is because of Bruce Lee. I think I am Chinese in my heart," says Freitas in the documentary.

"Another thing is about real fighting. Wing Chun is about how to finish fights very quickly and also how a small guy-or a woman-can deal with a very big guy," he explains.

In a quest to polish his skills and open his own martial arts school in China, Freitas has planned to stay in Foshan for six months.

According to local newspaper, the Foshan Daily, there are at least 52 kung fu styles in the city, being taught in nearly 300 martial arts schools. Those schools have spawned around 6,000 martial arts institutions in 176 countries and regions that boast in excess of 10 million total practitioners.

As a foreigner who loves Chinese culture, Freitas has picked liu as his new name. A Chinese character for the number six, it has a similar pronunciation to Leo, an abbreviation of his first name, Leonardo.

Huang Heshan, Freitas' fellow apprentice, says Freitas, who is married and has a daughter, is still childlike.

Huang adds that Freitas is very focused on practicing Wing Chun, saying that he is already well versed enough to open a school, but he still needs to learn more about Chinese culture and etiquette.

Approaching the end of the documentary, Freitas' dream is somewhat realized, as least for a moment, when he is taken by his master, He, to a local primary school to teach Wing Chun to more than 1,000 Chinese children.

"China is both an old and a modern nation. People know the essence of Chinese kung fu in many ways. I'm glad for this Shunde trip, which has strengthened my confidence to stay in China," says Freitas.

Producer Li Jianjun says the documentary will likely be aired by broadcasters within the Belt and Road Media Community to expand the popularity of kung fu in overseas markets.

As a global alliance of television media organizations, the community, which was launched in 2016, has now accumulated 130 members from 58 countries and regions.