Nian is trying to get into shape for the state Gaokao exam. Her chances of getting a spot at university depend on her score and the constant bullying of her classmates is not helping much. Bei’s world is the street, with all its dark corners. A night-time encounter brings the shy schoolgirl together with the street-savvy trickster, Bei. When Nian’s school nemesis turns up dead, the new allies come under suspicion.

In this tense thriller, Ma Shan (Wen Jiang) is a Chinese police detective who awakes one morning after a night of heavy drinking at his sister's wedding reception to discover that his gun has been stolen. Since only police officers are allowed to carry firearms, Ma Shan is alarmed about the deadly possibilities of the theft, and he sets out to find his weapon; however, the memories of Ma Shan's friends are as hazy as his own regarding the wedding, and no one can tell who drove him home. The situation comes to a head when Ma Shan's former girlfriend arrives in town for a visit and is soon found shot dead with the bullets matching those used in his gun.