America's favourite baby-sitters are detectives, too!
It all started with a simple prank, which Kristy thinks is the work of Cary Retlin. Cary denies it, but offers Kristy a challenge: The BSC has six days to solve eight of Cary's puzzle-like clues. If they succeed, Cary will stop his tricks. If they fail . . . well, Kristy hates to fail.
In the middle of the contest, SMS is hit with some real vandalism. Has Cary changed the rules, or has someone else - whose motives have nothing to do with fun - joined the game?