Heiji invites Conan to his kendo tournament but a drunk man named Atsushi Tarumi is found dead in the storage room. Heiji comes to investigate only to find that the body had somehow been moved to the shower room without anyone noticing. After a thorough investigation, Heiji reveals the culprit to be Takashi Kategawa, a friend of Tarumi. Heiji explains that in the storage room, Kategawa drugged Tarumi into a drunken slumber and put red paint on Tarumi to imply he was killed. After everyone leaves, he sets the scene to create the idea Tarumi committed a murder in his drunken frenzy. Tarumi heads for the shower room, suited in Tsuba Zeriai, in order to hide what he believed to be blood from the murder where he is then killed by Kategawa. As evidence, Heiji reveals that the mannequin that was used to trick Tarumi into believing he committed a murder was covered in red paint. After Tarumi is arrested, Heiji and Conan explore the town. Later a man is set ablaze atop Osaka Castle. After investigating thoroughly, Heiji and Conan concludes the murderer to be Shigehiko Wakisaka, one of the tour guides at the castle who committed the murders through the use of self-destructing flashlights. Wakisaka confesses and reveals that he was murdering his fellow tour guides who murdered his grandfather thirteen years ago. Arihiro Kasuya, one of the tour guides, confesses to have murdered Wakisaka's grandfather and prepares to kill Heiji but is apprehended by the police.