Kristy and the Cat Burglar — Ann M. Martin

America's favorite baby-sitters are detectives, too!

Is the Cat Burglar loose in Stoneybrook? The Baby-sitters think so. A cache of diamonds disappeared from a mansion while the security guard was called away, and the silhouette of a cat was stenciled on the mailbox. But other clues point to different conclusions, and the police have taken a very surprising suspect into custody. Now Kristy and her friends aren't sure whom to trust. Can they sort out the real leads from the fakes...or was this the purr-fect crime?