It's late in the evening as Chief Inspector Hanns von Meuffels (Matthias Brandt) finishes the paperwork to roundup his last case, and he's looking forward to a well-earned rest. However, a kerfuffle in front of the police station catches his attention. Elisabeth Strauß (Elisabeth Schwarz), resident of the Johannishof retirement home, is arguing loudly with the policeman at the gate. The vascular dementia patient is convinced that she has witnessed the murder of a fellow resident. Inspector von Meuffels, who seems to be able to connect with Frau Strauß, waits until the confused old lady's daughter arrives at the station. Since the daughter, Hanna Strauß (Therese Hämer), is quite obviously drunk, von Meuffels decides to take her mother back to the Johannishof residence himself.
Upon their arrival, the chief inspector learns that Karl Urban, another resident, was in fact found dead this evening. But as Tscharlie (Florian Karlheim), one of the three nurses, says, it's not unusual that people die here. However, after von Meuffels has examined the dead man's head injury more closely, he calls the crime scene investigators. The pathologist confirms von Meuffels's suspicion that the dead man could have suffered an unnatural death, although details will only become available with results of the pathological examination in a few days' time.
Von Meuffels remains in the retirement home in order to get an impression of what might have happened this evening as surreptitiously as possible. There's not much to be got out of the duty nurses Tscharlie Meier, Marija Abramovich (Marina Galic), and Sebastian Kroll (Philipp Moog), who are busy tending to their various tasks and give von Meuffels little chance to talk to them at length. Claus Grübner (Ernst Jacobi), home resident and former colleague of Meuffels's, makes a strange impression by letting his bitterness show and having little good to say about getting older.
Despite the difficult circumstances under which von Meuffels tries to get down to the truth, it doesn't escape his notice that the three duty nurses are hiding something…..