Cha wu ci xin

The discovery of a woman's corpse ironically saves the life of Wu Jie, a down-on-her-luck police detective whose life is falling apart. Soon more bodies and ominous clues emerge, revealing the work of a vicious serial killer targeting illegal migrant workers. With a local broker for the immigrants as a potential suspect, Wu Jie tenaciously pursues the case and finds herself vaulted from her own dire existential crisis into a harrowing realm of madness.