Brielle has to step into the position of principal cellist when her friend Tawni is injured. She's terrified. Is she good enough? Will the other musicians accept her? What if she screws up? Despite her fears, Brielle rises to the occasion, and she quickly begins to excel in her new role. But then Tawni returns. And she wants her job back. If Brielle steps down now, she'll lose her place in the stoplight. But if she doesn't, she may lose her best friend.