Jimmy Kudo, a 17-year-old high school prodigy and detective who frequently worked with the police, was attacked by two members of a mysterious crime syndicate while investigating a case regarding blackmail. He was then forced to take a newly developed experimental poison that was supposed to kill him, but due to a rare side-effect unknown to the two men, the drug transformed his body back into that of his seven-year-old self instead, after they left him for dead.[3] In order to hide his identity and investigate the whereabouts of the syndicate, which he later finds out is called the Black Organization, he adopts the pseudonym Conan Edogawa.[4] To search for leads to the syndicate, he manages to move in with his childhood friend Rachel Moore, whose father, Richard Moore, works as a private investigator.[4] He also enrolls at Teitan elementary school and forms the Junior Detective League with three other children in his class; Amy Yoshida, Mitch Tsuburaya, and George Kojima.[5] Even as Conan, Jimmy continues solving criminal cases, usually posing as Richard Moore with the help of special gadgets, invented by his neighboor and friend, Dr. Agasa. Richard Moore, a rather inept detective, is bewildered at the sudden rise in his case-solving abilities, but does not question this as he is more than glad about his subsequent rise in fame.
Later in the series, another main character, Anita Hailey, appears. A former member of the Black Organization, codenamed "Sherry", she is actually Shiho Miyano, a gifted chemist who developed the poison APTX 4869 which turned Jimmy back into a child.[6] After her sister was brutally murdered by members of the Black Organization, she tried to get out and was held captive.[6] She then attempted to commit suicide by taking a dose of APTX 4869, but instead was transformed into a child as well, and managed to escape from them.[6] She then enrolled in Conan's school under the pseudonym Anita Hailey.[6] She knows Conan's true identity and helps him in his quest to bring down the Black Organization.[6]
Later on, Conan becomes involved with the FBI, and they are able to capture Kir, a member of the Black Organization. Kir is later revealed to be an undercover CIA agent, and promises to relay information about the Black Organization to the FBI.[7] They return Kir to the organization. Later, she tells the FBI that the Black Organization has a new member codenamed Bourbon