Madden is getting used to living with his mother, an Army lieutenant, after having spent a lot of time with his grandparents while his mother was deployed. His father passed away when he was younger. Madden has diabetes, and even though he has a Continuous Glucose Monitor and manages very well, his mother is worried about him. Because he wants to play tuba in the school band, and his mother thinks this will stress his system, he gets a service dog to help monitor his condition. Zeus has been well trained, and does a great job keeping track of Madden's glucose levels and alerting him when they are too low or too high, but does have some behavioral issues. These stem from a series of misunderstandings-- Madden wants to fly "under the radar" at school and not draw attention to himself, but he loves music and is outstanding at playing the tuba, which leads Zeus to conclude that his mission is to "kill the music" in order for Madden to go unnoticed. This leads the dog to steal the teacher's baton, eat fund raiser food, and even attempt to ruin the instruments. Of course, this is NOT what Madden wants, and he struggles to understand why Zeus is acting out. He befriends Ashvi, a flute player with whom is assigned a duet for a concert, and she tries to help out with Zeus as well. Zeus's actions manage to get Madden in trouble with his mother, whom he is still trying to figure out. With a state contest looming, will Madden be able to control Zeus so that his group has a chance to win?