JJ MacGregor's very bad day has just gotten a lot worse.

JJ thought starting the day without coffee was a disaster, but now there's a dead musician behind the Pismawallops High School gym. His trombone is missing, and something about the scene is off key. JJ and Police Chief Ron Karlson are determined to get to the bottom of the mystery, but will they be able to work harmoniously or will discord ruin the investigation? With the music teacher as the prime suspect, JJ could be left to conduct the band, and then Graduation might truly end in a death by trombone, or at least the murder of Pomp and Circumstance!