Spring 1942. Moscow schoolgirl Katya is corresponding with a cadet of the naval school Kostya, who is unknown to her. When sent to the front, his echelon must pass through Moscow, and they have a chance to meet ... Our days. Muscovite Katya, a talented violinist and a wild child, without realizing it, begins to follow in the footsteps of the history of Katya and Kostya, her peers from the war years. Will she be able to finish an amazing teenage love story that began years ago?