In the Kingdom of Cavalon, ruled by lycanthropes who draw strength from the moon, King Valen Nightshade faces an impending war. Valen, known for his striking beauty and commanding presence, leads his people with strict authority, maintaining an uneasy peace with their rival, the Sora Dynasty—a human kingdom rumored to possess destructive magic.

When a series of coordinated attacks along Cavalon's border suggests Sora's involvement, Valen must confront the reality of looming conflict. Despite counsel urging negotiation, Valen refuses to show weakness and prepares for war, sensing a new and dangerous power behind Sora's actions.

As Valen makes difficult decisions, burdened by the weight of his kingdom's survival, the war begins. Little does he know that the path he is about to tread will not only plunge Cavalon into bloodshed but will also lead to his personal downfall—from a revered king to a feared villain. The eclipse of shadows foretells the transformation of both kingdom and king, as darkness envelops Valen's once noble heart.