A young girl is murdered near Opole. Terrifying body mutilations and marks left in place indicate ritual murder. The matter is being dealt with by Commissioner Agnieszka Polkowska. Due to the extraordinary cruelty of the crime and the suspicion that the perpetrator may be a serial killer, the case is interested in the Provincial Headquarters. Polkowska, to her dissatisfaction, is assigned to the investigation of Commissioner Tomasz Mrówiec.

At that time, Piotr Wolnicki, lectures on religious studies at the Opole university. He permanently works and lives with his family in a beautiful home. Already at the beginning of the academic year, the man chooses his humble and intelligent student Ewa Banach as his favorite. The girl does not know that her lecturer hides a dark secret.