A confused, 16-year-old girl is found in Dresden at night with a blood-stained scalpel. She reports that her father has kept her and her sister Jana imprisoned in a cellar for life, and that Jana is still there. Detective Winkler believes the traumatized teenager, while Schnabel has his doubts. Investigations and forensic examinations uncover evidence of family bloodstains – and suddenly Amanda herself is under suspicion of murder.

In the Black Forest, Detective Friedemann Berg discovers a frightened nine-year-old girl (Eliza) hiding in a clock case. Shortly afterward, her father's body, weighed down with stones, is found in a forest lake. His colleague Franziska Tobler and a child psychologist investigate, while Berg tries to help the selectively mute child overcome her trauma and find the missing mother.

During the final rehearsal of Haydn's "The Creation," a member of the props department is found shot dead at the opera house—posed as if in a stage production. A weapon from the costume department is missing. Ballauf and Schenk's investigation initially leads them to the singers, but soon a second murder occurs.

A toddler is found dead, his brother has disappeared. Stuttgart detectives Lannert and Bootz take up the investigation. At the center of the case is a family with a public past, whose internal conflicts increasingly come into focus.

Bremen detectives Moormann and Selb are investigating the death of a law student who was pushed down a flight of stairs near a nightclub. Their investigation focuses on her conflict-ridden shared apartment, a homeless suspect with her cell phone, and the immense pressure she was under to perform. The investigation uncovers a web of stress, family secrets, and shattered hopes.

Businessman Emil Feidt is found murdered in a village on the German-French border. The Saarbrücken investigative team, led by Chief Inspector Esther Baumann, investigates the case, which takes them to Baumann's hometown of Hohenweiler. They quickly suspect that the murder is connected to the unsolved death of Feidt's daughter five years earlier. Their investigation leads them into a web of long-standing feuds, guilt, and unspoken truths, further fueling the spiral of violence in the village and raising the question of whether evil is rooted in the individual or the community.

In Dortmund, several men are murdered in the red-light district – initially, it appears to be a power struggle. However, a deeper motive quickly emerges: the victims have false identities and are implicated in war crimes during the Yugoslav Wars. Detective Inspector Ira Klasnić reaches her emotional breaking point when repressed memories resurface and the State Criminal Police Office (LKA), led by Daniel Kossik, becomes involved.

Following the fatal accident of a bicycle courier who had shortly before been about to turn himself in, Lena Odenthal and Johanna Stern investigate on suspicion of murder. Stern goes undercover at his former courier service to uncover connections. This brings the internal structures of the collective business into focus, as well as personal motives.

Years after a high-rise fire that claimed 13 lives, Detective Hamza Kulina is reunited with his ex-girlfriend Almila, who lost her mother in the blaze. Evidence pointing to improperly installed insulation leads him and his colleague Maryam Azadi to a building materials manager with political connections – and puts them in danger.

They vow to each other not to be shot in their final case – a cliché Franz Leitmayr and Ivo Batic are determined to avoid after 35 years of service. But their farewell case turns out to be extremely dangerous: deep beneath the city, an unidentified woman's body is discovered. From just a few clues, the investigators piece together a perpetrator profile – everything points to a phantom who roams Munich apartments, targeting young women. Together with Kalli Hammermann, they build up the evidence against a suspect, but he always seems to be one step ahead. When they themselves become the targets, the finale raises the question of whether they can keep their promise.

Ivo Batic and Franz Leitmayr's retirement comes to an abrupt end when they learn that their last case was based on a lie. Kara Roth, the witness from back then, contacts them in a panic: she claims her life is in danger and that her statement was fabricated. Shortly afterward, she disappears. As private citizens, Batic and Leitmayr resume the investigation. Without official identification, they initially encounter obstacles, but then take advantage of the freedom they enjoy beyond police regulations. Their search for Kara, however, puts them in the crosshairs of powerful adversaries – and forces them to risk everything once again.

Frank Anders is the star of the cult children's show "Sachen und Lachen" (Things and Laughter), which he co-hosts with his wife, Caro. A well-established core team has been working on the show for years. But when cameraman Stefan Glück, nicknamed Happy, is found murdered in the trunk of his burned-out car, Ballauf and Schenk take over the investigation. It quickly becomes clear that a toxic work environment prevails behind the scenes. Frank Anders, in particular, dominates the studio and frequently clashes with puppeteer Yassin Meret – the perpetrator could be one of their own.