The Kowloon Walled City is a gray area of 30,000 square meters where 50,000 people are crowded. In the winter of 1984, 15-year-old Azu lost his father overnight - Blind Zhong was shot to death in the cold storage of the fish market because he refused to lend a way to the gangster Dongxing. All that was left to Azu was a hand-drawn map, a copper button torn from the murderer, a lame brother and a picked-up brother.
In this city with no laws and only rules, Azu started as a delivery boy and weaved homeless children into a mobile network, working step by step in the cracks between the elderly association, social groups and the police. He doesn't want to fight for territory, he just wants to keep the three words left by his father - you are the eldest brother. But when the shadow of Dongxing envelopes the city again, he must choose: continue to survive in the dark, or stand up and become a knife in the eyes of others.
