Once there was a girl named Harper who had a rare musical gift. She heard songs on the wind, rhythms on the rain, and hope in the beat of a butterfly's wing. Harper lives in the City of Clouds, an enchanting place where it rains every day and an umbrella is always a good idea. With her Aunt Sassy, her beloved cat, Midnight, and all of her neighbors in the Tall Apartment Block, every day is full of possibility. But when every cat in the city goes missing-including...