Zhang Diaoxian, Winston Chao, has already crossed into a realm beyond ordinary power, but he believes that achievement is not enough. He seizes the city of Hu and compels its residents to worship every word he speaks, weaving a web of loyalty that lets him pursue a darker, more ambitious dream. His plan hinges on a dangerous prize waiting in Hell: the Dark Crystal. With it, he intends to topple the existing pantheon of gods and rewrite reality itself, even if that means erasing countless innocent souls to fuel his scheme.
Not every demon in Hell accepts their fate or the hierarchy that binds them. Some crave redemption and a chance to redefine their lives, but they must keep quiet and play along while Diaoxian’s zealot demon-slayers hunt anyone who questions him. Into this volatile mix steps Kui, a local scholar who is manipulated by Diaoxian into becoming his most dangerous experiment yet: a pseudo-demon with the potential to slay demons more effectively than before. Kui’s difficult path becomes central to the city’s fragile balance, as Diaoxian wins the trust of Hu’s residents to hide his true intentions from both the living and the gods above.
Three years earlier, a snow demon named “Little Snow” (Li Bingbing) crosses paths with a younger Kui (Chen Kun) in a moment meant to seduce him. Her feelings complicate the plan, and she ultimately leaves when Kui declares that humans and demons do not belong together. Yet this encounter seeds a deeper collision of loyalties: Kui ascends through the imperial exams only to have his status stripped away by bribery, driving him to despair. Diaoxian revives Kui with a magical elixir, leaving him to believe he is still fully human even as he bears a growing demon-heritage.
As time passes, Kui works to master his new powers and, at Diaoxian’s command, steals the Dark Crystal from Hell. The Demon King, feeling betrayed and desperate, rallies his followers—along with some real demons—to reclaim the artifact and prevent Diaoxian from seizing control of Hu forever. In a strategic move, the Demon King revives Snow Girl to aid in the quest, while the Demon Sisters travel to Hu in disguise as traveling dancers. Their aim is simple and dangerous: to tempt the town into revelry and lust, softening the defenses that might guard the crystal.
Kui’s caution grows as he infiltrates their deception, feigning drunkenness to draw out the sisters’ true nature. A glimmer of romance rekindles between Kui and Snow, and for a moment the two share a private bond that makes the struggle feel personal rather than purely political. When their ruse is uncovered, a mystical fox guardian intervenes, and the lovers find themselves fighting on opposite sides. The conflict tears through Hu until Diaoxian arrives, and the demon sisters are defeated. Snow, trying to escape, is exposed in public, and Kui must confront a cruel choice: kill her to preserve the larger mission, or spare her to honor the vow they made to protect each other. He chooses mercy, but Diaoxian wounds Kui and Snow disappears into the maelstrom of the regime he has built.
Snow’s fate grows darker as Diaoxian intensifies his efforts to crush any resistance. Snow is captured once more, imprisoned in a crystalline structure high above the city, her life force weakened as the clock ticks toward a potentially centuries-long exile from Earth. Kui, wounded but unbroken, joins the Demon King’s forces in a bid to rescue Snow and end Diaoxian’s tyranny. Healing comes through stolen elixirs and renewed resolve, and Kui agrees to venture into Hell to confront the man who shattered so many lives.
The final confrontation pits Kui against Diaoxian in a clash of wits and strength. Kui’s demon form, forged by the pain of betrayal, presses toward the shattered center of Diaoxian’s illusion. The townspeople rally around Kui, turning away from the deceiving glow of Diaoxian’s spell, and Snow fights to break free from her crystal prison as Kui’s fury crescendos. The royal guard complicates the battle, forcing Kui to confront the remnants of his old allegiance, but he refuses to betray the people he now believes he must protect. With Snow’s life hanging in the balance, Kui shatters Diaoxian’s energy shield with a hidden blade, and Diaoxian is torn apart—four pieces, to be exact—exposing him to the world in a brutal, undeniable way.
The crystalline prison collapses, and Snow begins to fall. Kui catches her, but she is gravely injured and temporarily stripped of life as she drifts toward Hell to recuperate. The town’s faith in Kui’s rebellion swells as he slowly fights his way back to the surface, aided by the returning chi that the Dark Crystal helps restore to the people. Realization dawns on Hu’s residents: Kui’s resistance was not a blind act of rebellion, but a necessary correction to a corrupt order.
With the Dark Crystal in its rightful place, a new force steps onto the stage: the Jade Emperor himself appears and invites Kui to reincarnate, recognizing that the heavens still need him even as the world is rebuilt. The film closes on a hopeful yet tragic note: Kui dives back into the depths of Hell to seek Snow’s next rebirth, trusting that their bond can outlast the cycles of life and death. The ending leaves Hu saved for now, and Kui’s journey toward redemption—and perhaps a future reunion with Snow—continues beyond the screen.
