When you are over forty, you can put an end to your personal life, or you can give it a plus sign. It depends only on your own desire. Adelaida Maksimovna, the director of a provincial secondary school, was not strong in the arithmetic of love and did not hope for happiness, but she met it. Her chosen one is younger than her, handsome and so charming that it is impossible not to fall in love. Meanwhile, passions are boiling around Adelaide, because love has restored her youth and made her even more attractive than in her youth... What will come of this novel and will its characters pass the most important test - the test of fidelity?..