A case calls LKA investigator Maik Briegand to Lauchhammer, the place of his childhood and youth in the Lusatia lignite mining area. Here he meets his new colleague Annalena Gottknecht. A mysterious girl murder was committed. The first traces point to a sexual offense. Briegand and Gottknecht find out that the victim, Ramona Schinschke, was involved in drugs and had contacts with the local gang that officially sells magazines. Annalena Gottknecht, who meticulously types every detail into her computer, to Briegand's initial amusement, is confronted with the secrecy and stubbornness of her colleague during the investigation. Briegand determines intuitively. Again and again he meets acquaintances from his past. He started out as a young police officer at the Lauchhammer police station. For some, he is still "Maiki", the younger son of the police officer Karl Briegand, who was dismissed early from the service after reunification. While researching the victim's environment, Annalena comes across catastrophic conditions: Ramona Schinschke's mother has become addicted to drugs, her little brother Dustin is neglected and left to his own devices after Ramona's death. Only police officer André Pötschke takes care of the family... Juri Schavadenov, the victim's friend and member of the gang of crooks, is increasingly becoming the focus of investigations. When Maik and Annalena want to question him, he withdraws in a spectacular way.
LKA investigator Annalena Gottknecht believes her colleague Maik Briegand wants to protect a suspect, his old friend, the homeless Oliver Bartko. His DNA was found among others on the body. She begins to distrust Maik. Something from their past seems to connect the two men. Does it have to do with Oliver not being able to be in enclosed spaces? The 17-year-old murder victim, Ramona, had saved up a considerable amount from drug deals and had applied to the youth welfare office for guardianship of her little half-brother when she would soon come of age. The investigators find out: She wanted to get away with him - together with the suspect Yuri Schavadenov. There are conflicts between Briegand's former in-laws, who worked as miners, and his daughter Jackie, who is actively opposed to brown coal mining and has joined a group of climate activists preparing a major action on the edge of the open pit. Maik learns from his mother-in-law that Oliver is still working in her garden as before. Florian Langendorff, the new friend of his ex-wife Daniela, is anything but enthusiastic about this support. While Maik tries to rebuild the fragile relationship of trust with Oliver in the garden, Langendorff calls the police.
Homeless suspect Oliver Bartko is in police custody, panicking in his cell and rampaging. Investigator Maik Briegand can hardly bear to see his friend suffer. Against all regulations, he takes him outside so he can calm down. When Maik's colleague Annalena wants to take Oliver back to the cell, the situation escalates, with dire consequences.
The LKA investigators Maik Briegand and Annalena Gottknecht put Florian Langendorff, the friend of Maik's ex-wife, under pressure during the interrogation. Finally he admits that the murder victim Ramona sold him coke. But he denies killing her.
The publications about Ramona's death shocked Maik Briegand's father Karl, who was also a police officer. 30 years ago he investigated the "Katti" case. She was his son's childhood sweetheart and died under mysterious circumstances. Maik wants to know from his father why he is now dealing with Katti's death again.
During her research, LKA investigator Annalena Gottknecht came across other murders in the region that were not solved. All of the victims are young women who were strangled and from whom a sexual offense could not be ruled out - as with Ramona Schinschke, however, there were no genital injuries or traces of sperm in the young women.
