I Spy Castle is a puzzle game in which players get to explore a castle while playing I Spy type riddles and puzzles that test the brain. Players must win each of these puzzles to unlock new rooms of the castle in order to advance in the game. During the course of the game, players must search for and find over 400 items in 36 I Spy Riddles. There are also mini-games that helps to unlock the castle's intriguing secrets. The game features colorful graphics and realistic castle scenes of the princess' bedroom, the high turret, and the armory. The mini games allow players to shoot arrows like they did in the medieval times.