18. The Last People of Cologne

Ballauf and Schenk are investigating the violent death of a teacher. The young man was stabbed to death in cold blood in a park; the murder weapon was a hunting knife. The detectives quickly pick up a trail leading to the victim's sister, but she has seemingly vanished into thin air. She is believed to be part of the "prepper" community and to have gone into hiding at a survival workshop in a concealed bunker. While Ballauf and Schenk race to locate her hideout, tensions mount inside the bunker itself. Mistrust, fear, and hidden secrets create an oppressive atmosphere among the group, and the situation threatens to escalate.