Their friend Biff Hooper's disappearance at a survival game camp in Georgia leads the Hardy Boys to discover a training site for an elite corps of attack troops.
- ISBN10 0006945171
- ISBN13 9780006945178
- Publish Date 9 January 1995 (first published 1 September 1987)
- Publish Status Out of Print
- Out of Print 12 March 1997
- Publish Country GB
- Publisher HarperCollins Publishers
- Imprint Armada
- Format Paperback (A-Format (178x111 mm))
- Pages 320
- Language English