Frank and Joe Hardy, out ice-boating on Barmet Bay, receive permission to spend their Christmas holiday in a cabin on a small island. Strangers want them off it, supplies disappear in the night, and a lost notebook full of cipher and a trail of rare postage stamps lead the brothers toward a long-hidden secret.
The original 1929 text of an early Hardy Boys adventure, before the series was rewritten. Download the free EPUB.