The story begins with a voiceover highlighting the prominence of snake-style kung fu during its peak, setting the stage for a tale of fierce martial arts rivalries and personal growth. It introduces Hsia Sa, a notorious and ruthless fighter renowned for his mastery of snake-style kung fu; he was known not only for his exceptional skill but also for his viciousness and ambition to dominate the fighting world. Hsia Sa had left a trail of slain experts in his wake, fueling his desire for supremacy. One day, he challenges a monkey-style expert named Koo Ting-sang, leading to a legendary confrontation in the jungle.
As Hsia Sa patrols the dense greenery, he suddenly encounters Koo Ting-sang, who appears effortlessly from the treetops before jumping down confidently. The monkey-style expert questions Hsia Sa’s intentions, demanding to know why he has issued a challenge and asserting his readiness to kill him if necessary. Hsia Sa, without hesitation, declares that "today he will die," demonstrating his arrogance and bravado. Despite his confidence, Koo Ting-sang surprises Hsia Sa with his formidable skills, engaging him in a grueling and intense fight. Though heavily injured, Hsia Sa is not killed, and Koo Ting-sang chooses to spare his life — a gesture that underscores the complex honor and respect within martial arts traditions. Hsia Sa, bruised and battered, warns Koo that if he doesn't eliminate him now, regret will follow, but Koo, calm and confident, simply laughs off the threat, asserting that if he defeated him once, he can do it again.
The narrative then shifts to the story of Lung, a young, impoverished fishmonger with aspirations of mastering kung fu. After a late-night delivery to the wealthy Yan family, Lung becomes a victim of a savage assault by two of Yan’s sons, which leaves him humiliated and injured. The assault sparks Lung's desire to learn martial arts, prompting him to approach Teacher Ho, a skilled Hao-style kung-fu master who specializes in the Drunken style. Despite Lung’s desperate pleas, Teacher Ho initially refuses, claiming his school is full. To dismiss Lung, Ho tricks him into getting drunk, leading to Lung passing out. When Lung awakens, he finds himself in the countryside face-to-face with a deadly cobra, placing his life in imminent danger. Lucky for him, Koo Ting-sang, the monkey-style expert he once saw in action, comes to his rescue, saving him from the lethal snakebite.
Inspired by Koo's intervention, Lung manages to persuade Teacher Ho to finally admit him into the school, albeit as a modest "cleaner-up." It’s only after showing remarkable courage when being bullied by other students that Luo earns a spot as an official student. Later, Lung visits Koo Ting-sang with a heartfelt gift, expressing his gratitude for the monkey expert’s earlier act of kindness. In turn, Koo offers to teach Lung the advanced Monkey-style kung fu, but Lung, upon discovering that his instructor is actually a real monkey, declines the offer. Instead, Lung impresses Koo by demonstrating his newfound Drunken style skills during a confrontation with the Yan brothers, who arrive with intentions of seizing Koo's land. This act of revenge leads to the Yan family complaining to Teacher Ho, who, while displeased with Luo’s reckless behavior, becomes even more annoyed by their arrogant attitude. A fierce brawl erupts, leaving the Yan family humiliated and beaten, and prompting the Yan father to summon two Snake-style experts passing through the area for revenge.
Lung arrives at the school just in time to witness Teacher Ho being assaulted by the Snake-style assassins, Hsia Sa and his partner. Despite Lung’s effort to aid his teacher, the snake fighters prove too powerful, defeating Lung and killing Teacher Ho in the process. Barely conscious, Lung staggers to Koo Ting-sang, describing the attack and realizing the deadly retaliation from the snake fighters. Recognizing that Koo once fought and defeated one snake, he understands that these are personal enemies seeking vengeance, and the stakes are higher than ever.
Driven by a fierce resolve to avenge his mentor and Koo, Lung dedicates himself to intense training. The film depicts a series of grueling scenes where Lung practices balancing on pots, utilizing an elaborate rotating wooden dummy, and studying Koo’s master, a monkey, who kills a snake in a powerful display of kung-fu. Inspired by this moment, Lung devises a plan to blend the Monkey-style with his Drunken style, creating a unique fighting approach.
The climax delivers a spectacular showdown on an open, grassy terrain, where Lung faces the two Snake-style experts, Hsia Sa and his partner. In a symbolic gesture mirroring Koo’s earlier victory over the snake, Lung bites the hand of his opponent—demonstrating the same cunning and ferocity. An arduous and protracted battle ensues, testing Lung’s skill, endurance, and determination. Through perseverance, Lung ultimately defeats and kills both adversaries, avenging the deaths of Teacher Ho and Koo Ting-sang. His victory signifies not only personal growth but also the triumph of inner strength, courage, and the mastery that comes from relentless effort in the face of formidable enemies.
