While cleaning the shopping center as a class activity, Conan and the Detective Boys find a heap of garbage. It seems that there was originally a garbage bin there. At the store association, an argument is taking place over the garbage produced by the increased number of eateries and other stores, as well as the installation of garbage bins. Why is garbage accumulating in the location of the now missing garbage bin...? Meanwhile, the rest of the world, including Teitan High School attended by Ran and her friends, is buzzing with excitement for the WSG, an international sports festival held once every four years.