Cavaliers of the Starfish.

This detective story begins with an article in Ogonyok magazine about Soviet naval officers who were awarded the highest British award, the Order of the Star of the Sea, during World War II. After reading the article, the young heroine of the film named Olga, a resident of a small seaside town, realizes that one of these orders is kept on the mezzanine of her modest apartment, in a shoe box.