Conan Edogawa (江戸川 コナン Edogawa Konan?) is the alias used by Shinichi Kudo in his shrunken form. Shinichi took the appearance of his six or seven year old self after being exposed to a prototype poison called APTX 4869, which he had been forced to swallow by two men in black later revealed to be members of the Black Organization. The poison de-aged Shinichi's entire body except for his nervous system and therefore he still has the personality, memories, and incredible deductive ability of his teenage self. Conan's goal is to hunt down the Black Organization and have them arrested for their crimes, as well as find an antidote to the APTX 4869. To do so he plans to make the washout detective Kogoro Mouri famous in hopes of attracting cases related to the Black Organization.
Conan is often treated as a separate character from Shinichi by fans, and often viewed as the main character of the series while Shinichi is viewed as a recurring character. He has become a popular figure in Japan and even appeared at numerous occasions in different anime series (i.e. mainly cameo appearances) as well as other medias.
Conan enrolls at Teitan Elementary to further protect his identity and is befriended by classmates Ayumi, Mitsuhiko, and Genta, who create the Detective Boys not long after. In the beginning he found the kids annoying, but he started to warm up to them and even gives them missions to accomplice.
As Conan, Shinichi tries to behave like a child. He refers to Ran as "Ran-neechan" (nee-chan meaning older sister, a common nickname Japanese children give to teenagers and young adults they look up to), and refers to Shinichi as "Shinichi-niichan" (nii-chan meaning older brother). He also refers to Kogoro as "Oji-san" or "Occhan" (both meaning Uncle), although he also does this as Shinichi. As Shinichi, he refers to Conan as usually "Conan-kun" or the "Kid in the Glasses". Shinichi treats Conan as a separate person completely, thinking for example, "changing back into Conan".
Conan remains very close to Ran, who in return is very protective of him. However, because Ran is unaware of his true identity, Conan often finds himself in awkward situations with her, such as when she confessed her feeling for Shinichi to him and when she made him bathe with her at a hot spring.
Conan's intelligence remains intact even though he has shrunken into a child. As Shinichi, his deductive ability earned him the monikers "Heisei Holmes" and "Savior of the Japanese police force". Conan maintains an extraordinarily broad knowledge of many subjects and trivia that help him solve cases and escape tricky situations. Conan tries to speak in a child-like manner when dealing with adults, but he often gets caught up in the current case and begins speaking like an adult, referring to advanced topics and using reasoning much too complex for a normal child. When this happens, he often tries to pass it off as "something [he] heard on TV" or "taught by uncle Kogoro/professor Agasa/Shinichi-niichan".
Likewise, he makes no effort to hide his love for Sherlock Holmes and soccer, so if he called out for talking about either subject in too much detail, he tries to escape suspicion by saying it was something Shinichi told him about. Although as the series has progressed the adults around him have become more used to his "being quite smart for a child", causing him to behave more like himself around them, he still tries to pass as a normal child. The only police officers with whom Conan can speak in a professional manner are the FBI, especially Jodie Starling, Shuichi Akai, James Black, and Inspector Kansuke Yamato of the Nagano Police, all of whom suspect that there is more to Conan than meets the eye.
Conan tends to act more like himself around the Detective Boys, even to the point that they find it odd when he acts like a child around adults. He will often play games like baseball with the Detective Boys, but he is too used to soccer to perform well and will even instinctively use soccer techniques, such as kicking in games that do not call for it. Because he is unfamiliar with popular games and TV shows, and bad at video games, Genta and the others tend to think of him as dumb. This annoys Conan so much that he will secretly watch TV in the living room after Kogoro and Ran go to sleep to get more "practice" in.
While he thinks that criminals should be punished, he also seem willing to give culprits, who has attempted murder due to misunderstandings and fail, a second chance and let them off the hook.
After he had one time failed to stop the culprit from committing suicide, he began to believe that a detective who has cornered a killer and just let him kill himself is no better than a murderer, and therefore he tries to do everything to stop it.At times when he fails to save the killer it haunts him .