1911, A graduate of the Institute of Noble Maidens, Sasha Meshcherskaya returns to a small provincial town. The well-being of her family is based on her relationship with her loving uncle, the owner of the arms factory Nikolai Shumilov. Sashenka's parents: Prince Ivan Sergeevich Meshchersky and Maria Ilyinichna dream of their daughter's early marriage, and she herself dreams of a brilliant career as an architect. Wanting to please her parents, Sasha makes new acquaintances and instantly plunges into a whirlpool of intrigue, where political interests are at stake above personal passions. Cold-blooded murders and blackmail, intricacies of conspiracies, daring provocateurs eluding detection - all this captivates the enthusiastic schoolgirl, who experiences mortal melancholy from the paucity of life prospects. Without noticing it, Sasha becomes an ideal target for terrorist hypnosis.
The year is 1967. A series of mysterious murders of women are taking place in Leningrad. An experienced KGB major, Chuzhbin, and a police captain, Fedorov, are assigned to catch a maniac who leaves mysterious signs next to the victims.