

The act opens to find a group of Japanese nobles in characteristic attitudes. Nanki-Poo;still masquerading as a musician;returns to Titipu eagerly seeking Yum-Yum, as he has heard that Ko-Ko was condemned to death for flirting. He introduces himself, and, to his dismay, he learns from Pish-Tush that although Ko-Ko was indeed to have been beheaded, he was reprieved at the last moment and made Lord High Executioner instead. As the criminals must be executed in order, and Ko-Ko was next to be executed, no one else can be executed until Ko-Ko cuts off his own head.
For a small fee, Pooh-Bah, a ponderous aggregation of conflicts of interest, reveals that Yum-Yum is on her way home from school and will be wed to Ko-Ko this very afternoon.
The nobles herald the appearance of Ko-Ko and Ko-Ko appears and explains how he became the Lord High Executioner. He is full of ideas for his first official victim. He discusses with Pooh-Bah the plans for his forthcoming marriage.
The nobles herald the appearance of Ko-Ko and Ko-Ko appears and explains how he became the Lord High Executioner. He is full of ideas for his first official victim. He discusses with Pooh-Bah the plans for his forthcoming marriage.
A procession of school girls arrives, followed by Yum-Yum and her sisters, Pitti-Sing and Peep-Bo. Yum-Yum greets her betrothed decidedly less enthusiastically than she does Nanki-Poo. Ko-Ko introduces Pooh-Bah, who greets the girls very reluctantly. They respond teasingly.
Taking advantage of a few minutes alone with Yum-Yum, Nanki-Poo declares his love and shares with her the secret of his identity. Because of the excessive laws against flirting, Yum-Yum urges him to stay away from her. Nanki-Poo devises a plan to flirt by considering what they could do if it weren't for the law.
Ko-Ko, meanwhile, has received a letter from the Mikado, who is concerned that there have been no recent executions in Titipu and threatens severe repercussions if one does not take place within a


month, including reducing the town to the rank of a village. Although, as Pooh-Bah points out, Ko-Ko is next in line for that honor, Ko-Ko understandably would prefer to find a substitute. Ko-Ko, Pooh-Bah, and Pish-Tush debate who should be executed.
He comes across Nanki-Poo, who is preparing to terminate his existence rather than face life without Yum-Yum, and the two men strike a bargain: Ko-Ko agrees to let Nanki-Poo marry Yum-Yum now, and, in return, Nanki-Poo agrees to let Ko-Ko behead him at the end of the month and marry his widow.
The townsmen want to know how Ko-Ko will comply with the Mikado's decree. Ko-Ko introduces Nanki-Poo as his volunteer, and Nanki-Poo embraces Yum-Yum. All rejoice over this resolution, but the festivities are rudely interrupted by the appearance of Katisha. All cower except Pitti-Sing, who taunts Katisha. Katisha grieves her lost love. Furious at Nanki-Poo's rejection, she attempts to reveal his true identity. She is silenced by the crowd, but vows revenge.