The head of Magical Investigation, Jeiko Tatsuu, receives operational information about a visit to his city by a master-thief of the highest class. What he intends to steal is unknown, but many very influential people are behaving suspiciously. So what valuable thing has appeared in the city? So valuable that to get it, neither thefts nor murders are seen as a problem—exactly what Jeiko is trying to find out. As well as who is behind all these crimes.