In the middle of the day, after Ran gets off the phone from Shin'ichi, a teenage boy called ""The Great Detective of the West"", Hattori Heiji barges in the Mouri office demanding to see Shin'ichi (""The Great Detective of the East"") for a showdown.... (more) While Kogoro explains that he isn't here, a woman comes in asking Kogoro to help find her son's finance. They go to her house to discuss things further, when they see the woman they're looking for with her son. then when they get to her husband's office, they find her husband, a wealthy diplomat dead by poison. With the police on the scene with a locked door, they're baffled and determine it a suicide. Heiji thinking he gives the answers to Kogoro waits for him to show, and more determined than ever to solve the case before he does. Meanwhile, Conan, who has a cold, was given alcohol by Heiji to fell better, is now feeling worse...he feels like his body is on fire...what's going on??