The seventh-born rat of the seventh-born litter is always a rat in want of adventure. Tilbury is no exception. He just doesn't know it yet ...

The curse of a legendary diamond hangs heavy over the Dockland Rats - and it becomes clear only Tilbury can break the curse and save ratkind from disaster. To carry out his destiny, this timid young rat must leave the comfort of home for the very first time.

Tilbury's quest takes him to new lands, where huge cats and unfamiliar rats rule the streets and skies. Tilbury must risk everything to return the cursed jewel to its rightful owner ... and along the way, he just might discover what true treasure is.