Plot Introduction:
In the early 1990s, tractor factory worker Tietou (played by Jackie Chan), risking his life to smuggle himself to Japan to seek refuge with fellow villager Ajie (played by Nicholas Tse), in the hopes of finding his girlfriend Xiuxiu (played by Maggie Cheung), who went to study in Japan but lost contact. Tietou, like some other smugglers, does odd jobs at the dock and also engages in illegal activities for a living, during which he becomes entangled with the head of the largest local mafia, Jiangkou (played by Masaya Kato), gaining increasing power.
Unfortunately, due to past conflicts between Ajie and the leader of an external gang Gaojie (played by Gaoye), Tietou is dragged into the gang disputes; the police also name their investigation into the external gang's influence as the "Shinjuku Incident", investigated by officer Kitano (played by Naoto Takenaka)...