Arriving at the celebration of the engagement of Leonid Grigoriev and Irina Saiko, the invited Potapovs found the groom, the bride and their friends - Viktor Zhukov and the girl - killed. Bobrova and Pankratov were struck by the cynicism of the crime: an unknown person forced Zhukov to rape the bride, and the groom forced Zhukov's girlfriend, after which he stole jewelry and family photographs. Bobrova and Pankratov are developing a version of their personal hostility to the Grigoriev family, but a similar crime that happened indicates that a serial maniac has appeared in the city.