As the law states, Grace gets her bar code tattoo the day of her 17th birthday, although Eric, her crush, warns her against it. It appears that Global-1, a large corporation tracks people through a tracking device injected with the bar code. Grace, the daughter of the bar code invention, goes home to find that Global-1 is tracking her, forcing her to run and hide with Eric who is part of Decode, an underground organization who is battling Global-1. Members of Decode set out to do what they can to fight against Global-1 while trying to save people from a world wide devastating tsunami. This is the third book in the series, although it reads well as a stand-alone.