After losing her mother, thirteen-year-old Opal moves in with her uncle Roscoe on the family farm. There, Opal bonds with Uncle Roscoe over music and befriends a group of orphaned, music-loving bats. But just as the farm is starting to feel like home, the bats' cave is destroyed by a big mining company with its sights set on the farmland next.

If Opal and the bats can fit in anywhere, it's the nearby city of Austin, home to their favorite music and a host of wonderfully eccentric characters. But with people afraid of the bats and determined to get rid of them, it'll take a whole lot of courage to prove that this is where the bats--and Opal--belong.