Akari Gotou, a junior high bass trombonist, comes to the high school in search of Haruta and asks him to help her solve the puzzle of her grandfather's time abroad. Their clues include three paintings and a mysterious color called "Elephant's Breath."

The band club is growing. In order to get a budget increase, Chika and Haruta agree to track down one of the student council's problem club leaders. Why is the geology club leader on the run? What is her connection to a mysterious radio station?