At "Ruby's bar", the boss, Arlette Lesaffre, tries to talk to a young woman, Sarah Katzmann, sitting at the counter. Anxious, the latter is waiting for a man. A certain Morvan calls him: he cannot go to the bar. Communication is suddenly cut off because he is kidnapped at his home by three men. Meanwhile, Schneider and his two assistants are called to a city. They discover clandestine fights. Their arrival causes a crush in which a cop has his gun stolen, a Glock 19. The thief flees and Schneider sets off in pursuit, in vain. When leaving the bar, Sarah Katzmann is accused by Leay of drunk driving and aggression. Schneider is called to the scene because the young woman is a judge. He is opposed to Leray and decides to take her home. At his home, he discovers that his apartment has been ransacked. Sarah is not surprised: this is not the first time ...