At the beginning of the 20th century in Tokyo, the streets are rough, and the people yearn for a hero to emerge. Hirai Taro—who would later become the famed mystery writer Edogawa Rampo—harbors an intense admiration for foreign mystery writers, yet he is still an unknown author who is barely making ends meet by undertaking low-paying jobs. Despite bringing his manuscripts to newspaper publishers, Taro is completely ignored, until he meets Shirai Saburo, an elderly master detective full of humor and melancholy. His strength in the face of adversity impresses Taro, and in turn, Saburo is intrigued by Taro's eccentric ideas and moved by his boundless passion. The two form a partnership and embark on a journey into the world of detective work.