The Hardys head to Alaska to look into strange disappearances. They end up encountering men on a mission to steal US space technology. This is the original 1959 edition.
From inside the book:
The author proudly dedicates this book to the boys and girls of Alaska, which became our forty-ninth state during the writing of The Mystery at Devil's Paw.
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This is the unrevised, original 1959 edition of The Mystery at Devil's Paw.