[1][2][3] Sinn is noted for his roles as Sai-Mun Hing in The Reincarnation of Golden Lotus, for which he received Hong Kong Film Award nomination for Best New Performer.

[5][6][7] He had his first experience in front of the camera in 1986, and he was chosen to act as a support actor in Jeffrey Lau's Operation Pink Squad, an action film starring Sandra Ng, Guan Xiumei,[clarification needed] Ann Bridgewater, Elsie Chan, and Charlie Cho.

That same year, he participated in Tai Kit Mak's All Night Long, a story film starring Carol Cheng, Shui-Fan Fung, Elizabeth Lee, Elsie Chan, Crystal Kwok, and Wu Ma.

In 1993, Sinn had a minor role as Da Jiaoban in Wong Jing's City Hunter, which starred Jackie Chan, Chingmy Yau, Joey Wang, and Richard Norton.

In 1994, Sinn starred in a historical film called Fire Dragon with Brigitte Lin, Max Mok, and Sandra Ng, directed by Yuen Woo-ping.