In 2002, the first series started with the title of " Kyoto Kamogawa East Station Labyrinth Division Omiyasan ", changed the title from the second series in 2003 to " Omiyasan " In general cases, the case cannot be solved without catching the prisoner. It is like an unsolved case in which the exit cannot be found in a maze, which is called a "maze incident" by the police. The head of the Information Division of the Grass Wall Office (commonly known as the "Maze Division"), Kansaburo Torii, and his subordinate Yoko Nanao, use information of previous investigations to find the truth and solve the story of the pending cases that are about to expire.