Kogoro arrives in Okura, Fukuoka with Conan and Ran. Company president Fukamachi, his senior from his days as an MPD police officer, accidentally fell, and he's unconcious in the hospital. Managing director Kiriyama hires Kogoro to catch the culprit who graffitied the office. If Fukamachi is unable to return to work, Kiriyama will become the next president. Kiriyama believes Fukamachi's son Torahiko graffitied in the office in order to prevent that. Kogoro investigates the graffiti, but the possibility that Kiriyama pushed Fukamachi arises...