1904. A house on a hill in Nagasaki, Japan. 

Prologue

An American Navy Lieutenant, B. F. Pinkerton, purchases a Japanese doll.

Act I

Pinkerton inspects his new house, and Goro, a Japanese marriage broker, introduces the servants. Sharpless, the US Consul to Nagasaki, arrives, and the men toast to Pinkerton’s upcoming nuptials. Along with the house, Pinkerton has paid for an arranged marriage with Cio Cio San, a fifteen-year-old geisha known as Madame Butterfly.

Sharpless has concerns about the marriage: he is convinced that it means more to Cio Cio San than it does to Pinkerton. He fears that Pinkerton will destroy the young girl. Pinkerton tells him not to worry about the marriage. One day, he will “marry for real, a true American wife.”

Cio Cio San arrives with her relatives. She is from a noble family, but her father committed suicide at the request of the emperor. Having fallen into poverty, Cio Cio San has had to earn a living by entertaining men with song and dance as a geisha.

The wedding is a brief civil ceremony. As the guests celebrate and toast the new couple, the Bonze, a Buddhist monk, and Cio Cio San’s uncle, arrives in a rage. He reveals that Cio Cio San has recently converted to Christianity, forsaking her tradition and ancestors. The Bonze and Cio Cio San’s other relatives renounce her and depart.

Pinkerton comforts Cio Cio San. Suzuki, her faithful servant, prepares her for her wedding night. The newlyweds are left alone. As darkness falls, Pinkerton claims his butterfly.

Intermission

Act II

Three years later, Cio Cio San and Suzuki are on the verge of complete poverty. Soon after he married Cio Cio San, Pinkerton left Japan, promising that he would return in the spring “when the robins nest.” Suzuki tries to make Cio Cio San see that Pinkerton will never return. But Cio Cio San is certain he will come back and determinedly waits for him.

Sharpless visits with a letter from Pinkerton. Before he can read it to Cio Cio San, the wealthy prince Yamadori arrives with the marriage broker Goro. Yamadori knows that Cio Cio San has been abandoned by her husband and wishes to take her as his bride. She rejects his offer.

Yamadori leaves with Goro, and Sharpless again attempts to read the letter. He tries to reveal the truth ─ that Pinkerton has remarried ─ but he struggles to admit it, finally blurting out that she should marry Yamadori. Cio Cio San reveals she has given birth to Pinkerton’s son, and Sharpless promises to relate this news to Pinkerton.

A cannon-shot is heard from the harbor. Pinkerton’s ship has returned. Cio Cio San and Suzuki decorate the house with flowers. Cio Cio San waits up all night for her husband's arrival.

Act III

The next morning, Cio Cio San puts her son to bed. Pinkerton and Sharpless find Suzuki alone, and Pinkerton reveals that he is traveling with his new American wife named Kate. They want to take the boy back to America with them.

Remembering his life in the house, Pinkerton is wracked with guilt and flees. When Cio Cio San reenters, she looks for him, only to find Kate. Cio Cio San finally awakens to the reality of her situation. She tells Sharpless and Kate that she will give up her son if Pinkerton comes back in half an hour. Sharpless and Kate depart.

Cio Cio San ends one chapter and begins another.