Triggered by the disappearance of a brilliant young professor, this mystery takes the Hardy boys first to Kenworthy College, where they find a puzzling message on an examination paper. But then, a new clue is unearthed that sends the young detectives to the Honeycomb Caves. After many dangerous encounters, Frank and Joe discover a powerful searchlight in one of the craggy caverns along the seacoast. In the brilliant white glare of the searchlight, the startling secret of the caves is dramatically revealed.
| ISBN: | 9780448089072 |
| Publication date: | 1st May 1929 |
| Author: | Franklin W. Dixon |
| Publisher: | Grosset & Dunlap an imprint of Penguin Young Readers Group |
| Format: | Hardback |
| Pagination: | 192 pages |
| Series: | The Hardy Boys |