Shanghai King tells a story between a woman and three men, a story of conspiracy, a story full of love and hatred. At the beginning of the 20th century, Xiaoyuegui, an orphan from the countryside who lost her parents, came to Shanghai with her uncle and aunt to escape famine. In order to survive, she begged people on the street to buy her. However, by chance, during the chaos of the "Pujiang Chamber of Commerce" rescuing Huang Peiyu, she saved Yu Qiyang of the "Pujiang Chamber of Commerce". Thus, with the help of Yu Qiyang, Xin Daiyu of "Yipinlou" bought her for ten silver dollars as a maid. Unbeknownst to her, the legendary life of Xiaoyuegui quietly began at the moment she pressed her fingerprint.
At "Yipinlou", Xiaoyuegui met Chang Lixiong, the president of the "Pujiang Chamber of Commerce" and the King of Shanghai. Chang Lixiong was a man of righteousness and emotion. Although he was the King of Shanghai, he was willing to eat a bowl of "soup-soaked rice" made by Xiaoyuegui's own hands, which filled Xiaoyuegui with admiration and worship for him.
Chang Lixiong's affection for Xiaoyuegui made Xin Daiyu uneasy. She regarded Xiaoyuegui as a thorn in her side and conveniently married her off to Mr. Qin from Shandong, who came to redeem Xiaoyuegui. Xiaoyuegui refused to comply and fled from "Yipinlou" with the risky help of Yu Qiyang. Unfortunately, she was discovered by Mr. Qin, who failed to marry her and instead kidnapped her. At a critical moment, Chang Lixiong personally intervened and saved Xiaoyuegui, thus stirring up her youthful emotions. Despite opposition from everyone, Chang Lixiong married Xiaoyuegui. However, he was assassinated by Huang Peiyu at the wedding.
After the death of Chang Lixiong, Xiaoyuegui wandered in the countryside and gave birth on a stormy night...