Balkanski špijun (Balkan Spy) – 1984
Ilija Cvorovic is called by the secret police to routinely answer questions about his neighbour, businessman who had returned from the West. After that talk, Cvorovic is convinced that his neighbour represents the greatest threat to national security and begins his own surveillance operation against the innocent man.

Balkanski špijun – full movie

– let's put it in the list