Frank and Joe are headed out on a Kentucky spelunking expedition - exploring caves, that is. But Joe stumbles onto an uncharted subcavern, and suddenly the entire expedition is under attack. Can the Hardy Boys unearth the deadly secret at the bottom of this chasm of danger?
- ISBN10 0606093877
- ISBN13 9780606093873
- Publish Date 1 January 1996
- Publish Status Out of Print
- Out of Print 29 May 2021
- Publish Country US
- Imprint Turtleback Books
- Edition Turtleback School & Library ed.
- Format Hardcover (Library Binding)
- Pages 152
- Language English