Franklin W. Dixon 
The House on the Cliff [EPUB ebook] 
The Original Hardy Boys Series

The House on the Cliff (first published in 1927) is the second of the original Hardy Boys adventures.

When Fenton Hardy, the famous private detective and father of the Hardy Boys, asks his sons to help him with his latest case, Frank and Joe find themselves up against a ruthless criminal named Felix Snattman, whose business is smuggling stolen drugs.

Includes a new introduction by award-winning mystery author John Betancourt