16-year-old Fedya, who has been studying at an Orthodox boarding school since first grade, moves to his mother in St. Petersburg and goes to study at a regular lyceum. There he meets Pasha and Tanya, who open up a world full of unknown emotions, actions and places to him. Fedya falls in love with Tanya and cannot resist any of her desires. He is completely delighted with his new life and the possibility of teenage boundary violations until he learns that Tanya is in love with Pasha and they are planning to run away from their parents to Moscow. He is overcome with anger and envy, but a series of actions corresponding to the description in Christian theological books of the seven deadly sins make Fedor understand that it is the values instilled in the Orthodox boarding school that will save him.
