In 1960 a secret rocket launch occurred, preceding the first manned flight into space. The spacecraft is damaged before it enters the orbit and crashes in the remote, frozen part of the world. After he comes to his senses, he realizes that it is the year 2023, and he remembers almost nothing about his life before flying into space. His only memory is the image of a girl from the past. He knows her, but she doesn't know him...
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?