Griffin, a young bat, is sucked into the "Underworld," and his father follows to rescue him.
- ISBN10 1416949992
- ISBN13 9781416949992
- Publish Date 1 March 2008 (first published 1 January 2000)
- Publish Status Active
- Publish Country US
- Imprint Simon & Schuster
- Format Paperback (US Trade)
- Pages 336
- Language English