The Orpheum Cabaret Theatre in Budapest is overcrowded. The audience’s favorite performer Silva Varecsu is giving her last concert with her best act, Hungarian Csárdás Heia, o heia. During the interval two regulars Boni and Feri sing merry and cheerful songs including The Ladies up on stage. Prince Edwin appears. Boni passes him a message from his parents, where they demand that he breaks up with Silva. Edwin doesn’t respond. When he meets Silva, two lovers sing a dainty yet cunning duet Loveliness is all around us. Edwin receives an urgent wire from the colonel: he is being called up for military service. Edwin decides to take the last step and announces his marriage with Silva. The engagement ceremony is held at the Cabaret Theatre. The lovers sign the contract and the orchestra plays a wedding march (jolly variations on Mendelssohn’s famous Wedding March.
Edwin leaves after a tender farewell. Boni, who missed all the fun, shows Silva an invitation to Edwin and Stasi invitation ceremony. Silva’s heart is broken.
Vienna. A ball at Weylersheims’ palace. Being unaware that everybody knows of his engagement to Stasi, Edwin is concerned why Silva hasn’t responded yet. His numerous messages are left unreplied. Stasi knows about Edwin’s true feelings, but she doesn’t mind getting married to her cousin. They sing a careless duet.
Boni, Silva and Feri arrive to the ball. Boni introduces Silva to prince Weylersheim as his wife, countess Kanscianu and Feri as his father. Edwin, still confused, tries to check with Boni what happened, but Boni disappears. Edwin and Silva’s dramatic dialogue ends up in dreamy and plaintive waltz-duet Where are they now. Boni falls in love with Stasi and they sing a lively duet That fellow cupid.
Edwin’s father tries to announce their engagement with Stasi, but Edwin interrupts his speech and says he loves another woman – countess Kanscianu. However Silva renounces the fake title. She is not a countess, she is a princess, princess Weylersheim, which is proven by the contract. Edwin is ready to fulfill his obligation, but Silva tears up the contracts and leaves the palace.
Silva and Boni meet Feri after the ball. He tries to persuade Silva to return to the stage, because art will heal the wounds. Edwin is also here, he can’t do without her! His father arrives next. Edwin escapes and hides at Boni’s room. Prince Weylersheim wants to learn the truth. Feri meets the prince at the hall and tells him that his wife, princess Weylersheim used to sing at the cabaret as well. Moreover, she is the notorious Csárdás Princess, famous cabaret star High-Kicking Hilda. Upon her arrival to the hotel Stasi performs a cheerful duet with Boni. Edwin and Silva are reconciled. The operetta ends with a merry reprise Let me dance and let me sing performed by the lovers.