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.

Katya Alekseeva, handcuffed and with a plastic bag on her head, was found by her sister Lena. The girl was saved, but she refuses to name the attacker. According to the investigators' calculations, the unknown spent about an hour in her apartment, and an examination of the premises shows that there was another woman with Katya. The case is complicated by the fact that the victim claims that she was raped.