The school carnival is finally here, and it is packed with exciting rides, delicious treats, and fun games. Cam Jansen and her best friend Eric are having a blast exploring all the booths. But when Cam stops to watch the hardest game at the carnival, she notices something very strange. The best prizes are rapidly disappearing, and it does not look like anyone is actually winning them! Someone is sneaking away with the carnival's top rewards, and it is up to Cam to figure out how they are pulling it off. Luckily, Cam has the ultimate detective tool: a photographic memory. By simply saying Click! she can lock an image of the carnival crowd directly into her mind. Now, she must sift through her mental pictures to spot the sneaky thief before all the prizes are gone for good. Step right up and join Cam on a thrilling investigation filled with clever clues, quick thinking, and carnival fun.