Franklin W. Dixon
Book 68 of The Hardy Boys Mystery Stories
Language: English
Goodreads ISBN
Age Range 1 Younger Audience
On a visit to Germany, the Hardy brothers investigate the theft of plans for a newly invented submarine and the mysterious disappearance of valuable coins and paintings.
Description:
On a visit to Germany, the Hardy brothers investigate the theft of plans for a newly invented submarine and the mysterious disappearance of valuable coins and paintings.