In the conclusion of the search for the Golden Monkey, the Crypto-Capers, Granny, Max, Mia and Morris, find more than what they bargained for. From the very beginning, their resolve will be tested. Having found two of the pieces to open the treasure room in book 3, they soon come to realize they only have half of the puzzle solved. Their search for the other two pieces, will become more exigent. The Panther is hot on their trail, sabotaging them at every turn, like they had done to him in Chichen Itza. Feeling like he is close to finding the Golden Monkey, the Panther sends every accomplice he knows to thwart the detective team from finding the pieces, while at the same time, using their talents and knowledge for his own gain. In The Chest of Mystery the team will travel across the globe to Pisa, Italy where they will have to fight for their freedom, or be captured by the enemy. They must be one step ahead, but can it be done when the man who holds all the answers disappears without a trace? The Crypto-Capers list of friends begins to dwindle until they realize the answers are right in front of them, all they have to do is look, and believe. Their fate drops in the hands of one boy, Emmanuel Watson, whose history is tied to the chest, but can he find the strength to do what he must, especially when the world is against him? When so close to accomplishing their goal, obstacles arise, and the scent of betrayal is in the air.