A small Moravian town near Brno in the 1920s. In a forest clearing, the mentally disabled Fricek discovers three dead young people: the nineteen-year-old daughter of the local forest ranger Růžena, the butcher's assistant Hrnčíř, and the former student Roubal. Thus begins a detective story that screenwriter Roman Ráž wrote based on a true story. Inspector Vrba is in charge of investigating the case.

Jiří Bartoška, ​​in the role of police captain Hála, investigates the smuggling of hard drugs through a protected area in South Moravia. How does the military unit deployed in the border area and the strange behavior of animals around a nearby bear cave fit into the whole situation? This is answered by a television detective film made for a Brno studio in 1988 by director Rudolf Tesáček.