Use the decoder wheel to solve the mystery then turn the page for a whole new challenge. This exciting spy activity book has 18 pages of codes to crack and whodunits to solve. A few turns of the included decoder wheel-bound right into the book and visible from every page-will help young detectives complete each challenge as they put their deductive skills to the test. To uncover even more case-busting clues, sneaky double agents and hidden treasure, a magic-reveal pen is included, giving every page plenty of play value. It all stores neatly within the tab-close covers-perfect for spies on the go. Ages 7+.