Lin Yi, a former boxer who once fought in illegal boxing matches and caused her elder brother Lin Xiao's legs to be disabled, gave up boxing due to great guilt and self-doubt. She was constantly on the run to make a living and pay for Lin Xiao's medical treatment, and the two siblings thus fell into an irresolvable emotional state. In order to earn money, Lin Yi disguised herself as a man and applied for a job. Eventually, she became a sparring partner at the "Handsome Boys Boxing Club". During her interactions with the boss Song Ye, shareholder Gu Chenzhou and coach Han Xuan, her identity as a girl was at risk of being exposed many times. However, she didn't know that Song Ye and Gu Chenzhou had already discovered her true identity as a girl. Lin Yi managed to get through crises time and time again. Finally, she regained her true self, picked up her dream again, reconciled with her brother and achieved personal growth.
