Hopper never dreamed that there was a connection between the Bee School and her missing father--but it turns out that Albert Gracie was also a student of this mysterious coding school. His disappearance can only be the work of Dr. One-Zero. Dr. One-Zero, once a star pupil, is now a green-skinned villain on the hunt for the most powerful turtle in the world. It's up to the coders to stop him.