Su Can, a skilled general, leads a military campaign to rescue a prince captured in a heavily fortified mountain stronghold. In exchange for his bravery, the prince vows to ensure that Su becomes the governor of Hubei. However, driven by envy, Su's stepbrother Yuan wishes for Su's downfall. Despite this, Su offers to pass the governor's position to Yuan, aspiring instead to leave the military and dedicate himself to mastering wushu, with dreams of establishing his own school. As a token of their camaraderie, he gifts his prestigious sword to his comrade Ma and discusses his future plans with Yuan, who feels overshadowed but reluctantly agrees to take on the governorship. With a heavy heart, Su departs at dawn on horseback.
Fast forward five years, Su lives with his wife, Ying (Yuan's sister), and their child, Feng. Su's father brings unsettling news of Yuan’s return, cautioning that Yuan may be motivated by revenge, due to a tragic past where Su's father killed Yuan's father while unraveling an evil martial arts technique known as the Five Venom Fists. Despite his father's concerns, Su remains optimistic about Yuan's intentions.
A celebratory gathering ensues upon Yuan's return, where he meets Ying, Feng, and Su's father. Sensing the tension, Su’s father pleads with Yuan to seek vengeance solely on him, sparing Su and his family. However, in a brutal twist, Yuan uses his mastery of the Five Venom Fists to kill Su’s father, revealing a disturbingly deep desire to claim his sister and her child as his own family. When Su learns of this tragedy, he races to the scene but is ambushed by the Iron Twins. In a desperate chase and clash, he finds Yuan paying homage to his real father's shrine with Su's father's severed head as an act of vengeance.
A fierce duel unfolds, where Yuan's darkly reinforced armor grants him resilience against blades, and ultimately, he delivers a poisonous blow that leaves Su defeated. In a gripping moment, Feng pleads for his father’s life, which Yuan spares—but he tosses Feng into turbulent rapids. In a dramatic act of love, Ying leaps into the waters to save Su, leaving Yuan tormented by the loss of his sister. Heartbroken, Yuan takes Feng as his only remaining family.
Waking in a secluded forest, Ying strives to pull Su back to safety, aided by Sister Yu, a herbalist and winemaker who treats Su's grave injuries. When Su regains consciousness, he discovers that his arm has been rendered nearly useless due to extensive tendon damage. Initially consumed by despair and alcohol, Su's resolve steadies with Ying's unwavering support, inspiring him to train fiercely in hopes of rescuing Feng. During his training, he seeks guidance from the Wu Shu God and an ancient sage, dedicating years to mastering their teachings, but struggles to best the Wu Shu God.
Dr. Du’s diagnosis reveals to Ying that Su might be losing his sanity, suggesting that the mentors he believes in may be mere figments of his imagination. When Ying ventures into the woods and witnesses Su locked in a seemingly vain struggle against an imagined opponent, she implores him to return to reality, but to no avail. Too late, Su realizes the truth as Ying departs, determined to rescue Feng on her own.
Eventually, Yuan captures Ying in his palace. Upon his arrival, Su fights valiantly against the guards and confronts the Iron Twins, dispatching them with newfound skills. Yuan’s desperation leads to an ominous plot: he orders that Ying be buried alive and eliminates the men who carry out the deed, keeping her whereabouts a secret. A fierce confrontation culminates in Su battling a crazed Yuan in his training chamber, where Su ultimately vanquishes him, succumbing to madness in the process of delivering a fatal blow. As realization dawns upon him, Feng’s cry leads Su to rush out, but they arrive too late to save Ying from her suffocating fate, plunging Su into an abyss of grief.
Time passes, and the setting transitions from the dynastic era to one of colonial strife. Su, now unhinged from the weight of his losses, meanders the streets with Feng, who leads him by rope. While the Kung Fu community faces new threats, Ma has risen to lead the Wu Shu Federation following the death of a master in the arena. One fateful night, Su stumbles into an inn and wreaks havoc before meeting a fellow imbiber—appearing to be the Wu Shu God in disguise. Together, they engage in Drunken Fighting (Zui Quan) techniques, gradually restoring Su’s clarity.
When the innkeeper summons Ma, he recognizes the once-great Su, leading to a touching reunion. Ma, understanding Su's struggles, offers to watch over Feng, but the young boy refuses to leave his father's side.
The following day, the trio bands together for a challenge against foes in the arena. Su, oblivious to the brewing confrontation, enjoys himself at the bar while Ma faces severe odds. When Feng's cries for help pierce through the din, Su snaps back to his senses, sprinting into the arena just in time. Amidst chaos, he confronts and defeats an overpowering wrestler, and just when the tides turn desperately against him, he channels the spirit of his lost loved ones. With remarkable resilience, Su stands victorious, battered but triumphant.
In a poignant closing scene, Su, seemingly restored, begins practicing his wushu techniques once more, now with long hair that echoes his tortured past. Standing beside him are Feng and, in his perception, Ying, hinting at a rekindled passion and purpose.
