九頭竜館の殺人 (Kuzuryukan no satsujin)

The day after a seance held in an old mansion. In the back of the basement, the body of a psychic who claimed to have "witch's blood" was found. The suspects are a reporter, a university professor, a painter, a chauffeur, and the owner of the mansion, all of whom attended the seance and have different backgrounds. What shadow will the legend of the "monster that ruled the people in ancient times" that remains in this area cast over the case?