Shatterproof (The 39 Clues: Cahills vs. Vespers, Book 4)
Praise for The 39 CluesFeatured on NBC's Today Show, Good Morning America,  USA Today,The New York Times, NPR's Morning Edition, Associated Press"One blazing success." —The Huffington Post"An interactive mystery...it's more than just a reading adventure." —Boys' Life"This is a multi-media adventure where you also search for clues—in books, trading cards and online. Get searching!" —Girls' Life