A Fist Within Four Walls is a Hong Kong television drama created by Jazz Boon for TVB. It is a martial arts action serial drama, and revolves around kung fu masters living in the triad-ridden Kowloon Walled City during the early 1960s. The drama stars Ruco Chan as the series' protagonist, a gifted martial arts novice who, along with a group of young kung fu masters, take down the walled city's largest criminal organisation, the Fellow Association. The drama also stars Nancy Wu, Benjamin Yuen, Philip Ng, Yuen Qiu, Grace Wong, and Moon Lau in lead roles.
Chor Au-kuen (Chinese: 左勾拳; Jyutping: Zo2 Ngau1 Kyun4, meaning "left-hooked fist"), portrayed by Ruco Chan, is the main protagonist. He is often referred to as Kuen Lo (拳佬; "Fist Guy"; alt. "Boxer") by his friends, and is an extremely gifted martial arts novice. Kuen is described as an "optimistic and hot-blooded" natural-born leader, but is flawed with his impulsive and competitive nature. Kuen is kind-hearted, sometimes to the point of naivety. Yeung Hoi-pok portrayed 10-year-old Kuen.
Kuen was born Chiu Yeung (朝陽; Ziu1 Joeng4), and was the son of Chiu Mang-san, a Bajiquan master of the Chiu style. He and his younger sister Chiu Ha were both diligent Bajiquan students of their father. In 1945, when Yeung was 10, his family moved into the Kowloon Walled City to start a new living. They get acquainted with Duen Tung-tin, a Bajiquan master of the Duen style. Master Duen had long been a protector of the walled city; his Bajiquan kwoon was established to defend the walled city against oncoming triads, who were trying to take the ungoverned walled city as their base. Wanting to protect the walled city with them, Yeung asked his father to teach him his signature move, "Fierce Tiger Climbing Mountain" (猛虎硬爬山), but his father said the move was too powerful for someone as young as Yeung to learn.