The Unbreakable Code

Mr. Quisling is definitely up to something mysterious, and Emily and James are on high alert. First, there's the coded note he drops at a book event. Then, they uncover a trail of encrypted messages in Mark Twain-penned books hidden through Book Scavenger. What's most suspicious is that each hidden book triggers an arson fire.<br><br>As the sleuthing friends dig deeper, they discover Mr. Quisling has been hunting a legendary historical puzzle: the Unbreakable Code. This new mystery is irresistible, but Emily and James can't ignore the signs that Mr. Quisling might be the arsonist.<br>