Synopsis

ACT I

A war is on in the Duchy of Gérolstein, only no one knows why, let alone against whom. Nonetheless, Fritz, a young soldier, and his beloved Wanda meet to say goodbye before Fritz must go to war.  General Boum, head of the army and in love with Wanda himself, arrives and forbids Fritz and Wanda to see each other, a command which they promptly ignore. Baron Puck enters and reports that the war has been declared solely for the amusement of the bored Grand Duchess, who soon approaches.  Taking an impulsive liking to Fritz, she promotes the young private to Captain and dismisses the assembled.  Prince Paul, suitor to the Grand Duchess, arrives to take over for his unsuccessful messenger, Baron Grog, and pleads with the Grand Duchess in private to put aside affairs of state marry him.  Boum and Puck interrupt to explain their latest cockamamie battle strategy while Fritz, following behind them, suggests a more straightforward one.  His ingenuity gets him promoted to General-in-Chief, and the Grand Duchess publicly bequeaths to him her departed father's very own sabre.  Boum and Puck swear vengeance against Fritz, and the army sets off to war.

ACT II

The Grand Duchess' ladies-in-waiting read love letters from their soldier fiancés while Boum, Puck and Paul enter and begin to creatively plot Fritz's assassination.  Fritz and his army return triumphant, and the Grand Duchess wastes no time in confessing her love for him.  Fritz tells her that he loves Wanda and, worse yet, was hoping that the Grand Duchess would sign their marriage contract at that evening's court ball.  Furious, she summons Boum and Puck and swears to help deliver Fritz into their hands that evening when she gives the signal: Commanding the orchestra to play her grandmother's carillon.  That evening, the Notary arrives early to the court ball ready to marry Fritz and Wanda.  Fraught with indecision, the Grand Duchess eventually signs the marriage contract — but only just before striking up the orchestra in a rousing rendition of her grandmother's carillon.

ACT III

The Grand Duchess watches her band of amateur assassins as they enthusiastically ready themselves to kill Fritz, basing their plan on an old murder story that took place centuries ago in Fritz's lodgings. Once she reveals herself, she meets and takes a shine to Baron Grog who points out that, were she to marry Prince Paul, she would also be granted access to him.  Thrilled, the Grand Duchess announces that the assassination is cancelled; it would not do to have a murder take place on her wedding day. The group goes off its separate ways as Fritz and Wanda return to Fritz's quarters, eager to consummate their marriage. Before long, however, Boum and his crew break down the door and demand that Fritz return to battle — the enemy has made a counter-attack!  Distraught, Fritz goes off to do his duty.