Irena manages to gain the respect of the prisoners in her cell. Karolina and Michał trace the connections between the people involved in the murder in the den and discover who withdrew the money from the victim's account. At the same time, Karolina tries to decipher the data from the notebook father and reveals to Michał that he is conducting a private investigation. Together they reach an abandoned premises and find traces of a dangerous practice.

Irena is arrested. Her stay there is a shock, and her fellow prisoners seem hostile. Karolina, convinced of her mother's innocence, starts her own investigation. Meanwhile, Jagoda gives Karolina and Michał another clue in the case murders in the den. Karolina follows her father's recent affairs and makes a surprising discovery in her parents' house.

Karolina is an ambitious community police officer. She's trying to locate her father, a legendary Warsaw police officer, who has been missing for a year. His disappearance negatively impacts Karolina's relationship with her mother Irena and her sister Ewa. During a seemingly trifling intervention, Karolina finds a murder victim in a booze-den. Her search for the suspect captures the attention of Michal, a go-getting crime unit officer, while the disappearance of her father takes an unexpected turn.

The autopsy confirms the worst suspicions. Karolina and her sister try to inform their mother about the discovery of the body, but they cannot contact her. Is it possible that the woman knows much more than she claimed? At the same time, Karolina At her own request, she is assigned to investigate a murder in a den. He becomes acquainted with the suspect's girlfriend, Jagoda, who claims that her boyfriend was framed.