Cheng Xuan defeats former champion Lin Sen to become the first female boxing champion in history. However, during the award ceremony, she's exposed for using performance-enhancing drugs, causing public outrage. To escape, she hides her identity, adopting the name Chen Xuan, and flees with her mother. Five years later, Cheng Xuan arrives in Zhongxia City, working as a cleaner at Hengli Gym. She marries and has a child with Rong Yan, who goes by the alias Lu Chuan. Meanwhile, Wang Wei, the heir of the Wang family, tries and fails to win the heart of boxing coach Song Jiaojiao, later causing trouble at Hengli Gym. With some clever moves from Cheng Xuan, Song Jiaojiao successfully fights back. After his defeat, Wang Wei hires Jack, a nominal disciple of Lin Sen, to challenge Song Jiaojiao again. This time, she struggles, but just when things seem hopeless, Cheng Xuan steps in to save the day…
