Lieutenants Adam and Ditlev dream of being accepted into the Guard Hussar Regiment, and Captain von Rabenberg puts the two rivals to the test.

Doctor Falke takes revenge on Gabriel von Eisenstein because, after a carnival, he left him lying in a park, disguised as a bat, so that he would be ridiculed by respectable citizens the next morning. Falke seizes the opportunity for revenge when Eisenstein gets himself into trouble by being sentenced to ten days in prison for disrespectfully mentioning a princely person. The wealthy Russian Prince Orloffsky has asked Doctor Falke to arrange the entertainment for his grand party – and in this lavish setting, Falke carries out his revenge.