Series: 39 Clues Cahills vs Vespers

The Cahills were the most powerful family history had ever known... until they met the Vespers. Now the fight is on and the world hangs in the balance. 16 explosive evidence cards unlock a globe-trotting online mission. Follow the ancient trail of explorer Marco Polo and the warlord Kublai Khan to stop a Vesper plot — and discover their darkest...