Sin, a critic of the pro-democracy protests that hit the city in 2019 and an opponent of what he calls Western "hypocrisy" regarding Hong Kong, is a longtime kung fu practitioner.
A student of Ip Chun, the eldest son of wing chun master Ip Man, Sin became a filmmaker as a way of promoting the system through the Ip Man movies. He also has studied hung gar kung fu and the Chinese kickboxing style of san da and remains an active supporter of martial arts.
The March 27 election will be decided by a nearly 1,500-person committee of local electors made up of approved pro-Chinese government "patriots." Candidates for the city's leadership need nominations from one-eighth of the electors in order to run.
It's unclear if Sin has the necessary support, although it's believed his backing of government policies may earn his candidacy official approval.