Annie loves summer orchestra camp, and she works hard to keep her position as one of the top players in her section. But a new girl has come and all she wants to do is hike.So Big Mac, the conductor, assigns Annie to keep an eye on the new girl and make sure she shows up. It turns out the new girl, Ellie, is a super-talented string bass player with an important part in this year's final, Rhapsody in Blue.The dress rehearsal is tonight. But where is Ellie? Should Annie go to the rehearsal, or go find Ellie? And how can she find her, in the dark, in the woods? If they miss rehearsal, they won't be allowed to perform. But if Annie doesn't find Ellie, she could be in worse danger.