When blue-eyed cats go missing, it's up to a girl and her talking cat to solve the mystery and in so doing, they uncover a more sinister plot. This thrilling story continues where "The Lost Colors" left off. Rio, 11-year-old Caitlin Maggert's extraordinary cat is being honored by the Mayor for his role in stopping MacDougal, the infamous criminal mastermind. But Caitlin is worried about her darling cat - will he ever regain the full use of his superpowers? Rio is uneasy. He knows that McDougal is out there somewhere, and he, Rio must be strong enough and ready to protect Caitlin, her friends and family. Trudie invents a MacDougal Detection Device that will alarm if it senses MacDougal close by. Caitlin wishes that Special Agent Kate Becker and her team will hurry up and capture MacDougal. Rio watches Mrs. Brewster, their neighbor, and a woman immune to Rio's mind control, take Mr. Brewster's dog, Angus away to a kennel. This is very odd. Mr. Brewster adores his little dog. But Mr. Brewster is away on business. Rio doesn't think Mr. Brewster would approve. Then Caitlin and her friends discover a rash of lost cat notices all over town. Each cat is a blue-eyed cat. Except for Natalie Sherman's cat, Jellybean, who has one blue eye and one green one. Each cat owner confirms a single clue - a catnip mouse. Someone is stealing only blue-eyed cats by luring them away from the safety of their homes with a catnip mouse. Then Rio takes matters into his own paws and leads Caitlin and her mom to the truth. In so doing, Rio uncovers a sinister plot. They discover that the criminal mastermind will stop at nothing to capture Rio.