"Kagewani" is a suspenseful anime series that blends horror, mystery, and science fiction elements. The narrative centers on Sosuke Banba, a determined researcher investigating mysterious creatures known as "Kagewani," which are shadowy, monstrous entities that emerge under specific conditions. These creatures are often tied to human tragedies, environmental changes, or scientific experiments gone awry. Banba's quest to uncover the truth about the Kagewani leads him to confront various individuals and organizations with hidden agendas, including a powerful corporation that appears to be connected to the creatures' origins.

The series is structured in a monster-of-the-week format, with each episode introducing a new Kagewani and the circumstances surrounding its appearance. These encounters often explore themes of human greed, fear, and the consequences of tampering with nature. Banba's investigations are driven by personal loss, as his wife was killed by a Kagewani, adding emotional depth to his relentless pursuit of answers. Throughout the series, Banba's methods and morality are tested as he uncovers darker truths about the Kagewani and the forces manipulating them.

The animation style is distinctive, combining traditional 2D character designs with 3D-rendered environments and creatures, creating a unique visual contrast that enhances the eerie atmosphere. The pacing is deliberate, with a focus on building tension and suspense rather than action. The series maintains a consistent tone of unease, with each episode contributing to the overarching mystery of the Kagewani and their connection to humanity. By the end of the series, key revelations about the creatures and Banba's role in the larger conflict are unveiled, though some questions remain unresolved, leaving room for interpretation.