It is 1920. After three years of the Russian Civil War, communist government is finally established in Odessa. Young Volodya Kozachenko, who dreams of being a detective like Sherlock Holmes, joins the newly forming Odessa Criminal Police.

At the end of the Second World War, Fedor is demobilized and returns home where he meets a homeless boy, small Fedor. They decide to live together. The adult works in the building trade and the boy goes to school and looks after the house. They get on very well until Natacha arrives in big Fedor's life. After marrying big Fedor, Natacha tries to win the child's love. But he remains hostile.

Supply clerk Chuvilikhin goes to Moscow to fulfill his coworkers' errands. In the hustle and bustle of the capital, he loses the list where the name of the sheet music to be bought for the director's wife was written down. Anatoly Stepanovich rushes around the city trying to remember the melody.