While two criminals hide out at a woman's apartment after a botched robbery, an ex-cop tries to find a missing gun.

Cop-turned-security guard Ma Xianyong finds himself in a criminal twilight zone when two unrelated events turn his world upside down. The mysterious disappearance of his boss has implications for his financial security. Even more perilous is the abduction of his paralyzed sister who, unknown to Ma, makes a morbid deal with her captors.