In 1768, in the midst of a severe smallpox epidemic that killed every tenth inhabitant of the country, Empress Catherine II decides to set a personal example for her subjects: together with her heir, Tsarevich Paul, she is the first to be vaccinated against the terrible disease and declares vaccination mandatory for everyone - despite the court intrigues, peasant revolts and an impending war with Turkey, this decree must be carried out at all costs, otherwise the deadly virus will claim even more lives.