River Heights Elementary is throwing a fall festival! It promises to be full of fun games, great food, and amazing amusement park rides -- even a roller coaster! All of the kids in River Heights, including Nancy, George, and Bess, are very excited and have been working hard to earn extra money for festival tickets. So when Nancy's friend Ned claims someone stole his hard-earned tickets, the Clue Crew jumps into action. The girls are in a race against time to find Ned's tickets. And it turns out the culprit might have a very different reason for needing them...