dedication written inside
- Age Range: 8 - 12 years
- Grade Level: 3 - 7
- Hardcover: 192 pages
- Publisher: Grosset & Dunlap; 1st edition (December 1, 1966)
- Language: English
- ISBN-10: 0448089459
- ISBN-13: 978-0448089454
- Product Dimensions: 5 x 0.7 x 7.6 inches
Frank and Joe Hardy are determined to bring to justice the vicious criminals who kidnapped their detective father while he was investigation sabotage of a road-building project in the Kentucky wilderness. After Mr. Hardy’s escape, the two young sleuths are spurred into action when he mumbles the word “Felix” and they discover a dossier of a notorious ex-convict was stolen from his files. The trail leads them to New York City but ends abruptly in a cemetery! With the new clue of a spiral symbol the boys head to Kentucky as part of a highway construction crew to track down the kidnappers and saboteurs.