Golden Five by Goran Trencevski

Macedonian movie
Maki, Kata, and Jiji are loyal friends who believe in their youthful ideals. However, when Maki and Kata announce their engagement, Jiji becomes jealous. In the period of Communist liquidations, there is an unsolved murder of five students, one of them being Maki. A half-century later, Alavantie, as a witness and a researcher, returns to his homeland with the "Golden Five" dossier. His secrets and knowledge bring additional tension to Kata's and Jiji's married lives.

https://www.imdb.com/title/tt3468824/plotsummary/?ref_=tt_ov_pl