The year is 1984. At a house party, Nikolai Samoilov kills a woman. The guests immediately call the police, but the killer manages to escape. Moscow investigator Maxim Kovalsky (Maxim Stoyanov) calculates his location: Samoilov is arrested, and the metropolitan operative proves that this is the same maniac they have been looking for for the last two years and who has seven victims on his account. 

The year is 1989. Samoilov is in a psychiatric hospital and is being examined at the Serbsky Institute in Moscow. The famous psychiatrist Bazhenov treats him with a unique method, sincerely believing that the maniac will heal. And even prepares him for discharge, despite the fact that other doctors are against it. During the next transfer from the institute to the psychiatric hospital, Samoilov manages to escape. Almost immediately, a brutal murder takes place in the Moscow region. Leonid Ipatiev, an investigator for particularly important cases, is involved in the case. Kovalsky and Ipatiev begin to work together and try to find out if their fugitive has returned to the murders or if a new maniac has appeared in the criminal arena.

The year is 1984. The Byelorussian SSR. Leonid Ipatiev, senior investigator of the Minsk Prosecutor's Office, arrives in Vitebsk to investigate the case of the missing traffic police inspector. The inspector's body was not found, but the corpse of a young girl with signs of sexual assault and strangulation was found. Ipatiev finds out that 36 women have been strangled and raped in the Vitebsk region over the past 14 years, and all these cases were closed by Vitebsk investigator Mikhail Shakhnovich. Unprecedented statistics! Ipatiev suggests that a maniac is operating in the region. With the help of a young operative, Yura Mandrik, and a criminologist, Asi Krugovoy, Ipatiev initiates the resumption of the investigation, which causes a fierce confrontation between Shakhnovich: there is no sex in the USSR, and even more so sexual maniacs.