Viennese banker Heinrich Eisenstein committed a petty offense and must go to prison. But his friend Falk, the director of the local theater, invites him to the carnival given by Count Orlovsky. Forgetting everything, Henry deceives his wife Rosalind, saying that he is under arrest, and he and Falk go on holiday. Rosalind learns about her husband's deception and also goes to the ball to Orlovsky, disguised in a "Bat" costume and turned into a kind of "vampire woman" who is able to fall in love with her husband Henry and the influential Count Orlovsky ...