A car deliberately runs down a young man on a road by a small border town. The locals recognize the dead man as one of the students who were there on volunteer work some time before. The police detectives, Major Kalas (Rudolf HrusĂnskĂ˝) and Lieutenant Varga (Radoslav BrzobohatĂ˝) can then get on the trail of the people with whom the victim was involved, especially at the photographic studio headed by Bohuslav Pacer (Bohus ZáhorskĂ˝).