On the evening of June 11, 2009, a rape case occurred near the Friendship Square in Bengbu City. Two men on an electric bicycle carried knives to drive away Ms Xu's boyfriend, and then took Ms Xu to a house for raping her. One of the suspects even left a QQ number, claiming that he wanted to "keep in touch" with the victim. This QQ number became a clue for the Bengbu police to solve the case...