April 1959. Tanya Meshcherskaya, who grew up in an orphanage, goes to Moscow to her father, academician Vikenty Ryabinsky. She has a letter with her and an antique brooch inherited from her mother, which is stolen. Vikenty is happy to have a daughter, since he loved her mother, but his wife is hostile to Tanya. She tries to find out the details from Vikenty's sister, and she doubts that Vikenty is Tanya's father.