A plot to steal a top-secret instrument vital to the United States space program poses a challenging case for Frank and Joe Hardy. After rescuing a South American stowaway who mutters a warning about “Footprints “ and then vanishes, Frank and Joe discover that documents belonging to their famous detective father are missing and that footprints linger under a window. The young detective’s search for the diabolical mastermind of the “Footprints” spy ring takes them on a flight to a group of islands off the coast of South America.
- ISBN10 0448089122
- ISBN13 9780448089126
- Publish Date 1 February 1933
- Publish Status Active
- Publish Country US
- Imprint Grosset & Dunlap
- Format Hardcover
- Pages 192
- Language English
- URL https://penguinrandomhouse.com/books/isbn/9780448089126