Kudo Shinichi is a nationally famous high school detective. When he was tracking down a criminal gang of men in black, he was unfortunately discovered by gang members. After being knocked unconscious, he was fed a magical potion, and Kudo Shinichi turned back into a child! Shinichi found Dr. Agasa who often helped him, and the doctor tailored a lot of spy weapons for him. In order to prevent the criminal gang from retaliating against him, Shinichi decided to hide his identity and secretly track them down in the hope of getting an antidote. One day, Shinichi's girlfriend Mao Lilan came to Dr. Agasa's house to find her boyfriend's whereabouts. Shinichi, who was caught by Xiaolan, made up his name Edogawa Conan in a hurry, and then Conan lived in Xiaolan's house. Xiaolan's father Mao Li Kogoro is a private detective. Shinichi can track down the whereabouts of the night man by working with him to solve cases. Conan met elementary school students such as Ayumi in elementary school. Together, they organized a youth detective group to declare war on criminals!