The Jailers(1990)

A story about old people, the members of the secret society called Goethe, who feed on the energy of young men whose corpses are hidden in their laboratory. Even though police is on their trail, Goethe members manage to trick Pavle, the inspector-in-charge. However all of this energetic vampirism is busted when Kristina, one of the members, falls in love with the inspector.