Bir iblis tarafından büyütülen Akuma-kun ve yarı insan ortağı Üçüncü Mephisto, paranormal dedektifler olarak çalışarak çeşitli cinayetleri ve gizemleri çözerler.
Nearly twenty years into the 21st century, people have forgotten the existence of Yokai. When a number of unexplainable phenomena plague adults of the human world with confusion and chaos, thirteen-year-old Mana writes a letter to the Yokai Post in search of answers, only to be greeted by GeGeGe no Kitaro...
The story centers on Keitarou Gentouga, who has the ability to be a spirit medium. In junior high school, he got someone else wrapped up in a spirit possession incident, and he has been a shut-in for more than two years. As he reintroduces himself to society as a private tutor, he meets a genius girl named Yayoi Houzuki. Yayoi is instantly able to tell that Keitarou has skill as a spirit medium, and she invites him to go with her to a haunted location. The two then start their journey capturing evil spirits.
When a series of animal bodies that rot away after a single night begin appearing in a remote mountain village, Inugami, a detective from Tokyo who specializes in the occult, is called to investigate.
While working the case, he befriends a strange boy who works in the field every day instead of going to school. Shunned by his peers and nicknamed “Dorotabo” after a yokai that lives in the mud, he helps Inugami uncover the truth behind the killings — but supernatural forces are at work, and while Dorotabo is just a nickname, it might not be the only thing about the boy that isn’t human.
The Medicine Seller is a deadly and mysterious master of the occult who travels across feudal Japan in search of malevolent spirits called mononoke to slay. When he locates one of these spirits, he cannot simply kill it; he must first learn its Form, its Truth, and its Reason in order to wield the mighty Exorcism Sword and fight against it. He must begin his strange exorcisms with intense psychological analysis and careful investigative work—an extremely dangerous step, as he must first confront and learn about the mononoke before he even has the means to defeat it.
As customary per year, the entire family is gathering on the island for a conference that discusses the current financial situations of each respective person. Because of the family head's poor health, this year involves the topic of the head of the family's inheritance and how it will be distributed.
However, the family is unaware that the distribution of his wealth is the least of Ushiromiya Kinzo's concerns for this year's family conference. After being told that his end was approaching by his longtime friend and physician, Kinzo is desperate to meet his life's true love one last time: the Golden Witch, Beatrice. Having immersed himself in black magic for many of the later years in his life, Kinzo instigates a ceremony to revive his beloved upon his family's arrival on Rokkenjima.