Hank tries unsuccessfully to kill Walt, Walt Jr. takes it personally and steps up to become the new Heisenberg. On the day of his little sister's christening (I forgot her name, or when the family became Catholic, but whatever), Walt Jr. takes care of all the family business, i.e., has Hank, Skyler, Jesse, Marie, Lydia, Badger, Skinny Pete, and Saul killed. Breaking Bad II never really becomes a thing because there's nobody left for Walt Jr. to kill (I forgot, Walt Sr. died playing with little whatsername back near the end of Season Five), but we do see Walt Jr. brooding through a pane glass window or two, The End.