A young married woman, Liu Pingguo (Bingbing Fan), works in a massage parlor for sleazy Lin Dong (Tony Leung Ka Fai) and his infertile wife, Wang Mei (Elaine Jin). One night, Lin finds Liu drunk and rapes her, while her window-washer husband, An Kun (Tong Da Wei), helplessly watches. Furious, An attacks Lin's car and tries to blackmail him. When Liu discovers she's pregnant, the two couples come to an agreement: money for Liu if the child is Lin's, and nothing but custody if An is the father.