Aya Tachibana is a sixth-grader who frets and obsesses over friends, family, grades, and more. One day, she s the "Tantei Team KZ" with four very idiosyncratic boys she met at cram school. There is the glib and attention-grabbing leader Kazuomi Wakatake, the mysterious "expert of personal relationships" Takakazu Kuroki, the smart and stoic math genius Kazunori Uesugi, and the sweet-hearted Kazuhiko Kozuka who is good at social matters and science. Aya finds her place among them as the "language expert." "Tantei Team KZ" gets involved in modern-day cases, and even if they bicker from time to time, they collaborate by pooling each of their talents and skills to solve these cases. (Source: ANN)