Fernando loves Mozart, Puccini, and Strauss, and lending a paw at the old opera house. Unfortunately, diva Delores wants no help from a mouse. She craves glamour, spotlights, and praise, and she’s getting her chance to take center stage. But it’s all going wrong; she’s missing her entrance and flubbing her song. Will Delores hit a sour note—or can she and the opera house mouse make beautiful music together?