春秋时期，郑国庄公假天子命讨伐许国，以颖考叔为主帅，子都为副帅。子都争功心切，乘考叔将破许国之时，暗箭射死考叔。为赏子都灭许之功，郑庄公决意将考叔之妹颖姝嫁给子都，子都因“君命难违”无奈答应这门亲事。新婚之夜，颖姝泣求子都，为她找出杀兄仇人。子都夜夜恶梦精神崩溃身亡。

Kunqu Opera “Gongsun Zidu”, performed by Kunqu Opera Troupe of Zhejiang Province During the Spring and Autumn Period (770-476 BC), Lord Zhuanggong of State Zheng started a war against State Xu in the name of King. He appointed Yingkaoshu commander in chief, and Zidu vice commander. Zidu was so eager to win the battle achievement that he killed Yingkaoshu with an arrow from behind when State Xu was to be defeated soon. Lord Zhuanggong wanted to marry Yingkaoshu’s younger sister Yingshu to Zidu as a reward. Zidu agreed since he could not refuse the Lord. On the night of their marriage, Yingshu cried and asked Zidu to help her to find out who had killed her brother. Zidu had nightmares every night since then, and collapsed and died soon.