An adaptation of Johann Strauss′s operetta "Die Fledermaus": Dr. Eisenstein has been sentenced to prison after insulting an official. Without his wife′s knowing he wants to amuse himself at a ball on the night before starting to serve his time. His friend Dr. Falke wants to take this opportunity to take revenge for a mean joke Eisenstein once played on him. Therefore, he has invited Eisenstein′s wife Rosalinde to the ball. She enters the festivity dressed as a Hungarian countess and is promptly courted by her unsuspecting husband. This, however, is not the evening′s only charade: Since Rosalinde′s lover Alfred has to pretend to be Eisenstein, he is taken to prison in his place. The whole masquerade is only brought to light when the real Eisenstein reports at prison on the following morning.