"Götterdämmerung" is a manga series that intertwines elements of mythology, science fiction, and psychological drama. The narrative is set in a dystopian future where humanity faces extinction due to a catastrophic event known as the "Eclipse," which has plunged the world into perpetual darkness. The story centers on a group of individuals who are chosen to pilot biomechanical constructs called "Valkyries," designed to combat monstrous entities known as "Jötnar," which have emerged from the shadows to eradicate humanity.

The protagonist, Kael, is a young man burdened by the loss of his family during the initial outbreak of the Jötnar. He is reluctantly recruited into the Valkyrie Program, where he meets other pilots, each with their own tragic pasts and motivations. Among them is Lira, a fiercely independent and skilled pilot who becomes Kael's closest ally, and Ragnar, a veteran pilot whose stoic demeanor hides a deep-seated guilt over past failures. Together, they form a fragile alliance to protect the remnants of humanity.

As the story progresses, it becomes clear that the Jötnar are not mere mindless beasts but are connected to an ancient prophecy tied to the Norse myth of Ragnarök. The Valkyries, powered by a mysterious energy source called "Odin's Light," are revealed to be more than just weapons; they are vessels for the reincarnated souls of the gods themselves. Kael and his comrades must grapple with their own identities as they discover that they are the reincarnations of deities such as Thor, Freya, and Loki, destined to either prevent or fulfill the prophecy of the world's end.

The plot thickens as internal conflicts arise within the Valkyrie Program, with factions vying for control over the Odin's Light and the fate of humanity. Kael and his team must navigate these political machinations while confronting increasingly powerful Jötnar, each battle revealing more about the true nature of their enemies and their own divine heritage. The narrative explores themes of fate, free will, and the cyclical nature of destruction and rebirth, culminating in a climactic confrontation that will determine the future of both humanity and the gods.