The Detective Boys is a child gang of detectives. The gang was founded by Genta Kojima in the start of the manga. The Detective Boys were first Conan Edogawa, Ayumi Yoshida, Mitsuhiko Tsubabaraya and Genta Kojima, but later Ai Haibara joined the group. The kids help the police solve crimes. They often think too high of themselves and get into grave danger, but Conan always finds a way out.
Ayumi, Mitsuhiko and Genta know each other since kindergarden, and the boys have a crush on Ayumi. But Ayumi fell in love Conan when she met him, which makes Mitsuhiko and Genta jalous of Conan. Conan is the smartest one, of course, but it seems that the other kids are more clever than real kids at 7 years are. Ai is clever too, of course, but she isn't really in to the detective games like the others, she's more adult-like.
When the gang solves crimes with the police, Satou and Takagi are always surprised by Conan, who acts and speaks like an adult when solving crimes.

Will Ayumi, Mitsuhiko and Genta ever find out the truth about Conan and Ai?