Behind a moving staircase in an old Tokyo book shop lies the secret room of the City Jackers. This elite band of Tokyo detectives, backed by the powerful Oudou group, includes three remarkable kids. There's Jacky, a bishounen with a tongue like a chameleon, the pretty, but money-loving Maureen, and the fat Popeye, who loves writing haikus. The three of them work together to solve mysteries assigned to them by "Queen", a girl who contacts them via a video screen.