Lea Salonga is one of many who have starred as the title character (1999). A major role is that of "The Engineer", the Vietnamese pimp. There was a controversy when the production transferred from the West End to Broadway, because the British actor who had played the Engineer, Jonathan Pryce, was not allowed to take the role in the American production.
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It is an adaptation of Madame Butterfly. It tells the story of an American soldier, Chris, and a Vietnamese girl, Kim, who meet in a Vietnamese brothel during the final days of the Vietnam war, and fall in love. They go through a form of marriage, and Chris plans to take Kim back to the USA with him. The sudden evacuation of American troops forces him to leave her behind, not knowing that she is pregnant.
Kim brings up her little boy alone, and finds herself forced to kill to defend him against her vengeful cousin. She escapes to Thailand, where Chris eventually comes to look for her. During the years of separation, he has met and married an American girl. Kim wants them to take her son to a better life in the USA, but they are reluctant to separate him from his mother. In order to ensure her child's future, she kills herself.
See also: Shanghai woman