Mok Kwai-lan (Liu Xuan) is an ordinary girl working as a water labourer in one of Guangzhou's most famous restaurants. She lives in a simple and steady lifestyle with her uncle, Mok Ping (Law Lok-lam), and Ping's adopted son, Yau Sam-shui (Kenneth Ma). This simplicity is shaken when she meets the unsociable and eccentric young boxer Lui Ching-lung (Bosco Wong) in an underground martial arts arena, and the ambitious Kwai Fa (Fala Chen), an assistant chef who begins working in the same restaurant as her. Longing for Fa's affections, Sam-shui hopes to become a student of Wong Fei Hung (John Chiang), the greatest martial artist of Guangzhou, in order to impress her. Kwai-lan, originally uninterested in martial arts, becomes spellbound by the sport after watching an intense fight between Fei-hung and Fok Koon-wai (Kenny Wong), a Mizongyi practitioner.
Fei-hung is a man loved by the people, but his past had not been without causing offense. When Kwai-lan finds out that Ching-lung's father Lui Kong (Dominic Lam) is sick with leprosy, she asks for Fei-hung's help. However, Kong does not appreciate Fei-hung's hospitality and blames him for destroying his family. Twenty years ago, Kong was once Guangzhou's champion in the Lui Gar fighting style. Fei-hung, already famous for his martial arts in Foshan, challenged Kong to a duel. The two swore an oath: whoever lost the duel would have to leave Guangzhou. Fei-hung defeated Kong, but Kong's wife fell ill, postponing his leave. Fei-hung, drunk from a celebratory dinner, disgraced Kong in public and claimed him to be dishonourable for not keeping his promises. In a rage, Kong quickly leaves the city by night with his sick wife and their infant son Ching-lung. As a result, Kong's wife died and Kong contracted leprosy. Since then, Kong and Ching-lung had been struggling with discrimination and instability. Ching-lung, who had been kept in the dark about his family's history, is overwhelmed. When Lui-Kong, feeling guilty over his inability to provide for his son, decides to drown himself Ching-lung seeks revenge and attempts to kill Fei-hung in public. He is easily defeated, Fei-hung however apologises to Ching-lung for his mistakes and advises Ching-lung to pick up more martial arts before coming back for revenge.
Unknown to his son, Lui Kong is actually saved by Tong Yuet-hang (Elliot Ngok), Guangzhou's chief commissioner. Yuet-hang talks Kong in starting his life over, and suggests him to rebuild the Lui Gar martial arts school in order to compete with Fei-hung's Po Chi Lam. Yuet-hang actually has his own agenda, like Lui Kong he hated Fei-hung and wanted Lui Kong to publicly humiliate him. While Lui Kong recovers and prepares to re-establish his school, Ching-lung is touched by Fei-hung's generosity and decides to become his student. He develops a crush on Kwai-lan, and also wins the affections of Fa.
Fei-hung is touched by Sam-shui's enthusiasm and agrees to teach him and Kwai-lan, but Ping is strongly against it. He believes they would become aggressive and domineering if they learned kung fu. Kwai-lan disagrees and argues that kung fu is for self-protection. Her unyielding determination overwhelms Ping, and Kwai-lan learns from him that she is the only descendant of the Mok Gar family fighting style. As Kwai-lan's father died from a kung fu match, Ping does not want Kwai-lan to meet the same fate. Fei-hung sees a lot of potential in Kwai-lan and convinces Ping to teach her the styles of Mok Gar. Ping finally agrees, simultaneously allowing Sam-shui to become Fei-hung's student. Sam-shui, now proud and egotistical, begins abusing his newfound martial arts skill. This led to his involvement in a drunken brawl, and the death of Fei-hung's second son Wong Hon-yip (Raymond Wong). Initially charged with murder and to be executed, Fei-hung eventually realizes his son had been murdered by someone else and rescues him, but their friendship was forever ruined. Now hardened by life in prison, plagued by a prison record, jealous of Fa's love for Ching-lung and constantly looked down upon by the powerful, Sam-shui abandons martial arts and Fei-hung's ideals, instead striving to place himself in power first by becoming the increasingly powerful Lui Kong's head disciple.
Ching-lung and Fa had left Guangzhou in their efforts to find Lui Kong, and Fa was doing it only partially because she hoped to stay with Ching-lung and keep him away from Kwai-lan, who she knows Ching-lung had fallen for. When Kwai-lan unexpectedly visits them, she confesses to Fa she had actually fallen for someone, and Fa encourages her to go back to Guangzhou and admit her feelings while she and Ching-lung continued their search for his father. Kwai-lan does so, but not before telling Ching-lung that his father was actually still in Guangzhou. Both Kwai-lan and Ching-lung return to Guangzhou while a devastated Fa, rejected by Ching-lung, leaves by herself.
Amidst facing the threats and attacks against Po Chi Lam, Kwai-lan and Fei-hung grow closer. Kwai-lan not only helps Fei-hung in facing Kong's duel challenge, she also saves Po Chi Lam from collapsing. The two begin to fall in love, and Kwai-lan, being forty years younger than Fei-hung, marries him despite Ping's objections. Their happiness does not last long. Fei-hung, weak from an injury, is defeated from a duel against Kong and loses his title as Guangzhou's number one martial artist. Ching-lung, disgusted by his father's influence and still close to Fei-hung and Kwai-lan, chooses to stay in Po Chi Lam and allows Sam-shui to take his place in Lui Gar school. As he watches Yuet-hang and Kong's corrupted governance over Guangzhou, Fei-hung falls fatally ill. Before he dies, Fei-hung teaches all his knowledge of medicine and martial arts to Kwai-lan.
For more power, Sam-shui grows closer to Yuet-hang's office dealings and soon meet with one of Yuet-hang's strongest allies: the Japanese merchant Tokugawa Kazuo. When Kazuo visits Guangzhou, he brings with him Fa, the woman he had fallen in love with. The match seemed to meet all of Fa's hopes for a relationship, for Kazuo had wealth and prestigue, and soon Fa becomes one of the most public and influential women in town. Partially seeing her as an example and because he knew Fa would not give him any favors, Sam-shui marries Yuet-hang's daughter Shuet-kiu (Kaki Leung) and also becomes a spy for Kazuo. Soon Sam-shui gains control of all of Yuet-hang's business and political jobs, later becoming the co-mayor of Guangzhou. The Japanese merchants and fighters gain control of Guangzhou's economy and martial arts schools, forcing Po Chi Lam out of business. With his power secured and his enemies weak, Sam-shui starts to threaten and control Yuet-hang's family from the shadows. Kazuo, who had been blackmailed by Yuet-hang, was more than happy to help him. He felt a personal grudge against the Chinese martial arts schools, for he and Fa had almost gotten married before Ching-lung confessed his feelings for her. Despite all that Kazuo could offer her, Fa chooses a simple life with Ching-lung, and Kazuo was feeling particularly vindictive over his loss. In an attempt to protect himself and his daughter, Yuet-hang tries to release information of Sam-shui's secret collaborations with the Japanese to the public, but is murdered by Sam-shui before he could do so.
Kwai-lan, hunted by the corrupt police and Lui Kong's men, forced to flee and hide in Foshan with Ching-lung, returns to Guangzhou and wins in a fight with the Japanese martial artists, reviving the pride of Chinese martial arts. Despite opposed by Lui Kong himself, she hoped they could truly reunite all the martial arts school now, but Lui Kong is soon murdered for his possession of Yuet-hang's evidence against Sam-shui. He dies tragically, but had successfully hidden the evidence. Kwai-lan knows if anyone found it Sam-shui's life was forfeit and tries to convince him back on the right path. The two of them have a private meeting, Sam-shui admits that for the sake of their sibling relationship he could let her escape, but only her and she must swear to never interfere in his affairs. She refuses him, and both bid the other goodbye knowing one of them would soon have to die. Sam-shui, now too invested in Japanese imperialist ambitions, starts a fire to burn Po Chi Lam down to the ground in order to destroy any evidence of his wrongdoings. Because of this, the evidence was discovered, and although Fa took a bullet wound the proof was given to the national government.
Forced to flee for his life, Sam-shui demands that Kazuo help him escape to Japan. Kazuo, angry that Sam-shui had caused the Japanese residents in Guangzhou so much trouble in his attempts to discredit political enemies, ends up shooting Sam-shui instead. However Sam-shui survives, and almost manages to escape Guangzhou when he boards a train with Shuet-kiu. Perhaps to seduce her once more or perhaps because he did retain some humility, Sam-shui apologizes to her for all the trouble he had caused and admits that had she not been Yuet-hang's daughter he would have been kinder to her. Shuet-kiu tearfully admits that she had been happiest with him, but now that he had caused the death of her father and unborn child she could no longer forgive him. She stabs him to death in the train, the bloody scene was the last thing Kwai-lun will see of her remaining family since Shuet-kiu had told her she didn't want any relation to Sam-shui's relatives.
Kwai-lun moves into Hong Kong, meets up again with Ching-lung and Fa, and opens a school of martial arts, unprecedented of the time she takes in students of all ages and background. By doing this, she hopes to spread martial arts out to the rest of the world, fulfilling Wong Fei-hung's hopes of the future.
