When his parents return from Kenya with a cute little green lizard on his eighth birthday (he's two times two times two), Jacob Two-Two is thrilled. But it isn't long before Jacob realizes that his new pet, Dippy, isn't a lizard after all. And as months pass, it is apparent Dippy isn't so little either. Soon Dippy is attracting all sorts of unwanted attention, and before he knows it, Jacob is on the run from the Canadian government with a full-grown dinosaur to hide.