The film opens with a somber narration about the Samillian Tribe, once noble, now subjugated by the despotic King Laypach Billy Zane and condemned to wander the wilderness. The Samillians rise in rebellion under their mightiest warrior and holy leader, Draden Gabe Begneaud, who slays more than a thousand of Laypach's men. After a brutal twenty-three-year struggle, Draden is captured and beheaded. Yet before his execution, he prophesies that his spirit will descend upon a member of the Samillians, who will then lead them against their oppressors and toward the holy land of Promethea.
Eight years later, Grado Amurilus Drew Battles, son of the deposed king, lives as a farmer with his two boys, Magnus and Binon. Despite a century-and-a-half of oppression, their days feel almost peaceful as they share a simple life. Laypach, meanwhile, learns from his Wise Men that Draden's prophecy has come to pass and that the chosen liberator has begun to mature. They warn him not to allow the boy to unite with Draden's daughter Aria and to receive Draden's sword. If the chosen one uses the sword to pierce the ancient Stone of Groboda—blessed by the gods after it fell to the earth—Laypach will turn to dust. They tell him the chosen one's eyes will carry “the light” of Draden. The king disregards the counsel and orders the boy found and brought before him.
The Samillians continue their aimless trek through the wilderness, now accompanied by the Amurilus family. Binon clashes with Laypach's soldiers guarding the caravan, and a struggle erupts. Grado is mortally wounded, and Binon is captured. With his dying breath, Grado tells Magnus that he must free their people. After cremating his father in a small bundle of sticks, Magnus encounters a mysterious, magical chicken that reveals itself to be the small yellow wizard Gydro. Gydro speaks the spoken line, and Magnus's eyes glow with the light of Draden. Gydro falls to his knees, stunned and elated that he has found the appointed liberator of the Samillians. Magnus leaves him behind.
Magnus undertakes a period of fasting and prays to the moon gods, while the wise men return to Laypach with news of Magnus's whereabouts. Laypach summons his greatest warrior, the fearsome knight Kronin, to track him down. In the forest, Magnus meets a hunter named Ari and explains his quest to free his people. Although Ari refuses to discuss his past, the two decide to press on together.
Binon is brought before Laypach, and the wise men conclude that he is not the chosen one, though he is close. Binon is imprisoned in the dungeons, where he encounters a raving, deformed prisoner named Arden who taunts him. As Kronin tears across the countryside in search of Magnus, a blind fortune teller appears in the woods and prophesies that Kronin’s fate is “to kill and be killed.”
Meanwhile, Gydro visits Draden's daughter Aria and confirms that Magnus is the chosen liberator. Aria asks if this is truly the case, and Gydro confirms it. The princess and her four warrior handmaidens set out to find him, while Magnus and Ari share a meal with two mysterious women in the woods, who seem to possess supernatural abilities. Back in Laypach’s realm, the wise men are beheaded for their failures.
Ari trains Magnus in the ways of combat, and Kronin’s hunt intensifies as he encounters a blind fortune teller who deepens his own sense of fate. Aria and her group are attacked by bandits one night, and their handmaiden Derja is killed; they perform an ancient funeral rite as Gydro conducts the ceremony. Arden reveals why he is imprisoned: he once served in Laypach's army but refused to murder the wife of a soldier who had refused atrocities. Through flashbacks, it is revealed that the soldier is Ari.
Magnus and Ari eventually meet the same blind fortune teller, who confirms Magnus’s destiny as a mighty warrior with a great future. Kronin returns to Laypach in shame, lamenting the difficulty of locating someone who hides in the dense forests. Laypach becomes frustrated and orders Binon taken from the dungeons to guide them to Magnus.
Magnus and Ari cross paths with Aria’s group again, and Magnus is instantly smitten. Gydro reappears and confirms Magnus’s identity as the Samillian liberator. He places Draden’s sword in Magnus’s grasp, and it glows blue when Magnus holds it. Later, as the group camps, Sina, one of Aria’s handmaidens, attempts to seduce Magnus in the hopes of becoming his queen; Aria witnesses this treachery, and Sina curses them before fleeing into the woods.
That night, Ari stares at the moon, mourning his dead wife. Magnus brings him back to the camp, where Gydro is dying. He warns them that the Stone of Groboda lies a half-day’s journey to their left and that Kronin is closing in. Gydro dies, and Ari pledges to lead the remaining path forward.
The following morning, Kronin discovers Sina exhausted in the woods and she betrays the group out of jealousy that Aria referred to Derja, not Sina, as her sister. Arden curses the king from his cell. Magnus, Ari, Aria, and the remaining handmaidens reach the Stone of Groboda just as Kronin and his soldiers arrive, with Binon in chains. Kronin demands their heads, and a fierce battle ensues. Ari and the handmaidens strike back, but both handmaidens fall. Magnus frees Binon from his chains as Ari battles Kronin; Ari falls, dying with visions of his wife.
Magnus and Kronin continue their duel, and Magnus finally defeats the evil knight. Using Draden’s sword, Magnus pierces the Stone of Groboda, triggering a massive bolt of light that blasts Laypach’s distant throne room to dust. Arden’s deformities melt away as the tyrant’s power collapses. The Samillians celebrate their newfound freedom, and Promethea finally comes into view just beyond the woods. Magnus and Aria share a quiet kiss as Binon jokes about starting a karate school, earning a hint of humor amid the triumph.
