there is a moment when he starts calling her a bitch - very out of character for him - that Skyler's eye looks to the FBI agent in her home (left, recall, logic), then up and to the right, getting creative. She starts playing along with the lie, and at one point even AGREES with Walt that she doesn't know a single thing about his business.
He is smart enough to know the police are there - a kidnapping was made from his home with 911 on the line. That call was entirely to clear Skyler and let them know hank was in the ground and it was all on HIM and him alone. Nobody caught that on the Talking Bad show - finally, host Chris hardwick had to blurt it out in the closing seconds of the show, and Hank actor Dean Norris confirmed it. Walt took all the blame. You could see tears running down his face... Has to stop to collect himself. This is his 'goodbye' call.
NOW - He runs and lives in New hampshire for 6 months... returning only to Save someone with that ricin in the finale....
So I'm guessing (only 2 episodes left)... This week he runs to NH and hides... Then in the final episode, he wishes himself a happy 52nd BDay at a Waffle House, picks up his weapon (ricin) and then sits down and poisons himself along with the targeted bad guy (lydia tea??)
I'm predicting Walt dies on his 52nd Birthday.
