Griffin, a young bat, is sucked into the "Underworld," and his father follows to rescue him.

"Kenneth Oppel's compelling prose and Chris Steininger's dynamic illustrations work seamlessly together to reintroduce Shade to readers young and old. Shade is a young silverwing bat, the runt of his colony. But he's determined to prove himself on the long, dangerous winter migration to Hibernaculum, millions of wingbeats to the south. During a fierce storm, he loses the others and soon faces the most incredible journey of his young life. Desperately...