In "Tip Top," a confidential informant from Algeria has been murdered. Esther Lafarge(Isabelle Huppert) has been assigned the case. She chooses Sally Marinelli(Sandrine Kiberlain), who had been demoted to internal affairs for personal reasons, to be her assistant. Together, they investigate the case, starting by talking to the victim's wife Virginie(Karole Rochar). Robert Mendes(Francois Damiens) takes another angle, by recruiting Younes(Aymen Saidi) to be his new informant. "Tip Top" is an offbeat political mystery that is as interested in who the victim was as who the murderer is. In this immigrant milieu, reflected by rioting simultaneously occurring in Algeria, the movie is very much interested in identity. So, investigating are two women who are not so strange for their sexual fetishes but for other reasons. Sally might not have a personal identity of her own and has to copy others while Esther might just be a vampire. That being said, they still go out and do their job in the most professional way possible.