"Teito Ayakashi Daihitsutan" is a manga series set in an alternate version of Tokyo during the Taisho era, blending historical elements with supernatural and occult themes. The narrative revolves around the city of Tokyo, which is under constant threat from malevolent spirits known as ayakashi. These entities are drawn to the city due to its rapid modernization and the resulting imbalance between the spiritual and physical worlds. To combat this threat, the government establishes the Ayakashi Hunting Bureau, a specialized organization tasked with protecting the city from supernatural dangers.

The protagonist, Shizuki, is a young man with a mysterious past and a unique ability to see and interact with ayakashi. He becomes a key member of the Ayakashi Hunting Bureau, working alongside other skilled individuals who possess their own supernatural abilities. The team includes characters such as the stoic swordsman Kujuro, the enigmatic medium Ayame, and the brilliant but eccentric scientist Dr. Kuroki. Together, they investigate and neutralize various ayakashi threats, uncovering deeper conspiracies and hidden truths about the spiritual world and its connection to Tokyo.

The plot is structured around episodic cases, with each arc focusing on a specific ayakashi or supernatural phenomenon. These cases often tie into a larger overarching narrative involving the origins of the ayakashi, the true nature of Shizuki's abilities, and the Bureau's role in maintaining the balance between the human and spiritual realms. As the story progresses, the characters face increasingly powerful and complex adversaries, leading to revelations about their own pasts and the dark forces manipulating events from behind the scenes.

The series explores themes of coexistence between humans and spirits, the consequences of rapid industrialization, and the moral ambiguities of wielding supernatural power. The setting is richly detailed, blending historical Tokyo with fantastical elements, creating a vivid backdrop for the unfolding drama. The interplay between the characters, their personal struggles, and their evolving relationships adds depth to the narrative, making "Teito Ayakashi Daihitsutan" a compelling blend of action, mystery, and supernatural intrigue.