The Hunt for the Missing Spy — Penny Warner

Cody, Quinn, Luke, and M.E. are the Code Busters--clever clue hunters with a passion for puzzles.

When the Code Busters head to Washington, DC, on a class trip, it's the perfect opportunity to hone their sleuthing skills. Especially when the itinerary includes a trip to the International Spy Museum.

Setting off on a coded clue hunt across the city to landmarks like the Washington Monument, the White House, the Lincoln Memorial, and the Air and Space Museum, the gang has all the right skills to take the lead.

But someone disguised in a trench coat and dark glasses is right on their heels. And when a classmate goes missing, the secret spy may be the key to solving the case.

This interactive mystery features more than fifteen coded messages and puzzles to decipher including the code George Washington used during the Revolutionary War, the Freemason Code, and the Vigenére Cipher used by Confederate soldiers.