Clarence and his friends live in a neighborhood of older, but well-kept brick homes in a typical American town. They like to ride the bus, hang out at the shopping mall, eat fish and chips, and surf the Internet. It has come to their attention that a necklace owned by Mary Ann Bennett is actually a long-lost heirloom belonging to a very wealthy family. The necklace was given to Mary Ann for her birthday by her five-year-old brother, so at the time it was assumed to be a cheap trinket. Unfortunately, by the time the truth about the necklace is discovered, a small dog has inadvertently obtained possession of the item and run off with it, hitching a ride on a delivery truck. Clarence and friends, with no time to lose, decide to "borrow" a car and follow in pursuit. The odd thing about this? Clarence and his friends are cats!