One Nite in Mongkok (2004)

The accidental death of a gangster's son during a drunken altercation ignites tensions between rival gangs. Officer Milo leads a task force to investigate, uncovering a plot to assassinate the rival gang's leader. As Milo and his team race against time to prevent a violent street war, Lai Fu, an ambitious yet inexperienced hitman from a rural area, arrives in Hong Kong, ready to fulfill his deadly assignment. The intertwining fates of Milo, Lai Fu, and the gangs set the stage for an explosive showdown in the city's underbelly.