Self-proclaimed grandmaster Ma Fei Lung (Dayo Wong) is the 19th-generation successor of his family's Thunder Fist martial arts. One day, he gets knocked out by a woman on the street in full view of the public. His embarrassing defeat is captured on video and goes viral. Overnight, this "grandmaster" becomes a laughing stock. Fei Lung learns from a journalist that the woman who beat him has an impressive background. She is none other than the Hong Kong legendary boxer, Chan Tsang (Annie Liu). Chan holds a record of 40 consecutive victories. In an attempt to salvage his reputation, Fei Lung issues Chan a challenge on the boxing ring. Fei Lung's ex-wife Mei (Catherine Chau) repeatedly has him wrapped around her finger and causes him to be devastated. As a result, Fei Lung is unable to focus on his preparation for the fight. With the challenge approaching, what will Fei Lung do?
