Legend of the Millennium Dragon

The film opens with a brutal clash between samurai and smoke-wreathed Oni. Monastic Gen'un unleashes a surge of magic to wipe out the demons and save a village temple from destruction. The scene establishes the high-stakes conflict that frames the story.

Shy teenage Jun Tendo is suddenly hurled 1200 years into the past, landing in the Heian era as war rages between humans and Oni. He feels out of place and scared as the threat of pursuit tightens around him. His disorientation marks the start of his long journey.

Jun flees into the temple garden when an Oni closes in. Inside the temple, Gen'un and the skilled swordsman Raiko Minamoto reveal the stakes of the conflict and explain why Jun's arrival matters. The revelation begins to set the terms of the conflict and Jun's role.

The villagers begin to treat Jun as a savior, flattering him despite his uncertainty. He wrestles with trust as loyalties shift in a world where friend and foe can blur. He must decide who to trust.

As night falls, Oni assault the temple and the villagers rally to defend their home. Jun finds himself drawn into the defense and realizes his presence has meaning beyond himself. The defense tests his courage for the first time.

Jun discovers a birthmark on his left shoulder tied to the Magatama clan, a sign that can awaken the legendary dragon Yamata no Orochi. In a surge of power, Orochi awakens and he rides the dragon, becoming its ally.

Jun meets Mizuha, an Oni who defies simple good-vs-evil labels. She explains that Oni are people who wear masks, and reveals how nobles have driven Oni from their homeland, forcing both sides into fear.

Mizuha latches onto Orochi and escapes with Jun, but they are halted by a mysterious anti-Oni barrier. Jun regroups with Raiko’s fellow swordsmen Tsuna and Kinta, who have been searching for him.

Gen'un’s true schemes come into sharper focus as a temple councillor is exposed as manipulated by the monk. Jun confronts Gen'un with the truth about his crimes, triggering a fierce clash between Oni and humans.

Raiko, under Gen'un’s control, is transformed into one of the Four Heavenly Kings, a mind-controlled warrior. Jun’s appeals to Raiko’s memory and grief begin to loosen the hold long enough for him to act.

Mizuha provides Jun with two crucial artifacts — a gem containing his true power and a dagger given to Raiko in childhood. When placed together, they merge into a sword that becomes Jun’s conduit of strength. This weapon is the key to facing Gen'un.

Gen'un amplifies his power, transforming the Four Heavenly Kings into a single monstrous form and waging a devastating attack. Jun channels his inner resolve and calls upon Orochi to unleash its full might, with Yamata no Orochi revealing its final form to defeat Gen'un with a water-based surge.

The climactic battle ends and Jun awakens back in his school uniform, carrying the memories and confidence he gained in the past. He returns to his life with a quieter strength and renewed purpose.

The tale ends on a note of reconciliation between the worlds, suggesting that understanding and empathy can bridge divides when one dares to listen to both sides. The story leaves Jun with a sense that courage and empathy can shape real change.