Marina is 40, she is married to an architect Vadim, and everything seems to go well. Sveta is the half-sister to her. She is a 20 years old woman and she has a baby, Sonya, she wants to refuse from. Unfortunately, Marina is infertile and she thinks that the baby refreshes her marriage. However, Vadim leaves Marina for his pregnant mistress. After the partition process, Marina receives the flat, which is currently at the groundwork stage. Because she is an architect by profession, she decided beginning working as an architect. After all bureaucratic obstacles, Marina finally adopts Sonya, half-sister's daughter. Two years later Marina feels happy: she raises Sonya, has a good job and mutuality feelings with her client Andrey. However, Svetlana, half-sister, suddenly appears in Marina's life again.