Ottoline lives in a stylish apartment in Big City with a small hairy creature called Mr Munroe. Together they look after the Brown family's eclectic collections - and dabble in a spot of detective work. So they are the first to the scene of the crime when a string of high society dog-nappings and jewel thefts hits Big City. Ottoline (who luckily has a diploma from the Who-R-U Academy of Disguise) and Mr Munroe go undercover - and expose an ingenious scam masterminded by furry feline crook, the Yellow Cat.