Billy is busy boasting about how well he plays Marcus's new medieval castle video game. He is so keen to prove his ability that he plays during class, but he gets caught by Mrs. Snodgrass, who confiscates Marcus' game forever. Earl fondly remembers the world's first video game, which he invented. He, too, had been caught playing in class and had his computer game confiscated, robbing Earl of all his video game fame and glory. Earl becomes increasingly angry over his lost opportunity, and he turns the school into the game ""Wolf Castle 3D."" The gang counts on Billy to see them through, since he knows the game so well. Facing villain after villain, Billy is finally forced to confess that he never played the game at all, and that he doesn't know a thing about it. Luckily, Marcus does know the game -- very well, since he created it. Billy, Lydia, Marcus and Ruby work together to hack into Earl's computer and turn the school back to normal.