Master Yo wants Yang to start using his brain to fight bad guys, but Yang isn't interested. An old floating skull villain named Mastermind sees a way for him to use Yang's non-interest of using brain power to his advantage. Mastermind tricks Yang into giving up his brain, and Mastermind's brain now takes over Yang's body! With Mastermind controlling Yang, he can fulfill his plans for world domination. Yang will have to figure out a way to use only his brain in order to get back to the Dojo and get his body back before sundown.