Cabin Creek Mysteries #1: The Secret of Robber's Cave Paperback – March 1, 2008 by Kristiana Gregory 
Book 1 of 10: Cabin Creek Mysteries
 
Action! Intrigue! Cliff-hangers! With a riveting overarching series storyline and a mini-mystery in each title, Cabin Creek gives readers what they crave: immediate answers AND ongoing suspense. Every book reveals clues, adds layers, and finds the characters investigating, plotting, and unraveling clues. They'll need their wits, their courage, and their gadgets to get to the bottom of the many mysteries of Lost Island.

Jeff and David's dad told them they weren't allowed to explore Lost Island until Jeff's twelfth birthday, and that they should never go alone.

As soon as they set foot on the marshy ground, they suspect something is not right. What secrets are hidden by the lingering mist and overgrown pines? The brothers had never believed the Legend of Robber's Cave, but now they have to wonder. And when their nine-year old cousin, Claire, convinces their parents that she should be part of the island outings, things get more complicated.

Should they believe Mr. Wellback's warnings? Is there an actual cave? Did the stagecoach robber really die there? And did he take the secret of the treasure with him to his grave? The cousins plan to find out, but they soon realize that the truth is harder to uncover than the skeleton of an escaped villain.

This is #1 in the series.
 
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