Count Cagliostro, performing magical shows as he tours Russia, is forced to stay for some time at the estate of a provincial nobleman. There he meets a young man who is in love with a marble statue and — wanting to conduct a psychological experiment — promises to bring it to life. At the same time — as part of another experiment — Cagliostro tries to make the young Mar’yа Golovina fall for him “by scientific method,” having deceived her and taken her away from her parents’ home.