"Saint Seiya: Soul of Gold" is a 13-episode anime series that serves as a spin-off to the original "Saint Seiya" saga, specifically set during the events of the "Hades Arc." The story centers on the Gold Saints, elite warriors who serve as guardians of Athena and the Sanctuary. After sacrificing their lives to destroy the Wailing Wall in the Underworld, the Gold Saints unexpectedly awaken in Asgard, a realm connected to Norse mythology, rather than facing eternal rest.

In Asgard, the Gold Saints discover that their Cloths, the armor they wear, have been imbued with a mysterious golden light, granting them enhanced powers. They soon learn that their resurrection is tied to the machinations of Andreas Lise, the self-proclaimed ruler of Asgard, who has manipulated the realm's sacred tree, Yggdrasil, to siphon energy from the Gold Saints' Cloths. This energy is being used to sustain his tyrannical rule and corrupt the land.

The Gold Saints, led by Leo Aiolia, must navigate the challenges of Asgard, confront Andreas' forces, and uncover the truth behind their resurrection. Along the way, they encounter familiar faces, including Lyfia, a kind-hearted maiden with a connection to Yggdrasil, and the God Warriors of Asgard, powerful adversaries who serve Andreas. Each Gold Saint faces personal trials and battles, reflecting on their pasts and reaffirming their dedication to protecting Athena and justice.

As the story progresses, the Gold Saints uncover the deeper connection between Asgard and their own destinies. They learn that Yggdrasil itself is a sentient entity, and its corruption has dire consequences for both Asgard and the world beyond. The climax involves a final confrontation with Andreas, who has fused with Yggdrasil to become a god-like being. The Gold Saints, united and empowered by their resolve, unleash their full potential to defeat Andreas and restore balance to Asgard.

The series concludes with the Gold Saints fulfilling their purpose and returning to the afterlife, their legacy as protectors of Athena and the world reaffirmed. "Soul of Gold" expands on the lore of the Gold Saints, blending the established "Saint Seiya" mythology with Norse elements, while emphasizing themes of sacrifice, camaraderie, and the enduring spirit of the warriors.