The typical Kochikame plot involves Ryo-san coming up with a money-making scheme by inventing a new gadget or capitalizing on a fad, achieving great success, calling on Nakagawa's help as things turn sour, and finally losing it all as the fad runs out of steam or out of control. While the plots are gag-driven, much of the humor comes from the combination of mundane characters with the bizarrely out of place characters as Nakagawa who has wealth and Maria who has appeal. What they have in common is everyone's lack of actual police work, most of which is never explained or rationalized in the slightest. (It is explained in Jump that Ryo-san is one of the best officers in catching criminals.) Reiko and Nakagawa have special licenses from police headquarters because of their skills in linguistics.