Patti Randall (Hayley Mills) is the owner of a curious cat who comes home one day wearing a wrist watch. The girl contacts the FBI when she thinks something suspicous is happening and Agent Benson (Roddy McDowall) is assigned to tail the cat to try and find out where the wristwatch came from. The bumbling FBI agent hopes the cat will also lead him to the location of a kidnapping. Comedy ensues as all the charecters are involved in the cat's hijinks and a bit of romance is also involved with the characters.