On whether the writers considered a version in which Jesse does shoot Walt during their final conversation
“We talked about Jesse taking Walt up on his offer to kill him or Walt turning around to find Jesse had a gun on him. We talked about every permutation we could conceive of, and we went the way we went ultimately because the bloodlust had been satiated prior to that moment by seeing Jesse throttle Todd (Jesse Plemons) to death. That’s what the writers wanted to see. Todd is actually in a weird way kind of likable, but he just had to go. Opie had to go. Ricky Hitler, as we like to call him. I think the whole world is better off without that group of characters. So having satisfied that, it felt to us like, ‘Jesse is not a killer.’ This poor guy has wound up having to kill over and over again. The first time he did it was to save Mr. White as well as himself, and it’s not a natural fit for him, and it’s something that’s stolen a big, important piece of his soul. And we thought to ourselves, ‘You know what? Let it end with Todd. Let that be the last person this kid ever kills. Let him go on from here to have a decent life.’ And also, he’s got reason enough to kill Walt. He’s got reason enough to be murderously angry at him. But he had said a long time ago, in a previous episode, ‘I’m never doing what you tell me to do ever again,’ so when he says no and drops the gun and says, ‘Do it yourself,’ to Mr. White, it’s as much a refusal to do what Walt tells him. He’s just not going to make Walt happy anymore. It’s not about, ‘I’m not still angry enough to murder you.’ Rather, it’s, ‘You want this, and therefore I’m not giving it to you.’”
On the story inspiration for Walt, who was hellbent on killing Jesse, saving his ex-partner out of sudden instinct
“A lot of astute viewers who know their film history are going to say, ‘It’s the ending to The Searchers.’ And indeed it is. The wonderful western The Searchers has John Wayne looking for Natalie Wood for the entire three-hour length of the movie. She’s been kidnapped by Indians and raised as one of their own, and throughout the whole movie, John Wayne says, ‘I need to put her out of her misery. As soon as I find her, I’m going to kill her.’ The whole movie Jeffrey Hunter is saying, ‘No, we’re not — she’s my blood kin, we’re saving her,’ and he says, ‘We’re killing her.’ And you’re like, ‘Oh my god, John Wayne is a monster and he’s going to do it. You know for the whole movie that this is the major drama between these two characters looking for Natalie Wood. And then at the end of the movie, on impulse, you think he’s riding toward her to shoot her, and instead he sweeps her up off her feet and he carries her away and he says, ‘Let’s go home.’ It just gets me every time — the ending of that movie just chokes you up, it’s wonderful. In the writers room, we said, ‘Hey, what about the Searchers ending?’ So, it’s always a matter of stealing from the best. [Laughs]“
On whether Walt’s death means that he ultimately paid for his sins
“It’s in the eye of the viewer. Dying is not necessarily paying for one’s sins. I certainly hope it’s not, because the nicest people that have ever lived are going to die eventually. So it could be argued instead that he did get away with it because he never got the cuffs put on him. [There was] the one time with Hank [Dean Norris, in 'To'Hajiilee']. But he’s expired before the cops show up. They’re rolling in with the sirens going and the lights flashing and he just doesn’t give a damn. He’s patting his Precious, in Lord of the Rings terms. He’s with the thing he seems to love the most in the world, which is his work and his meth lab and he just doesn’t care about being caught because he knows he’s on the way out. So it could be argued that he pays for his sins at the end or it could just as easily be argued that he gets away with it.”
On how Lydia became the ricin target
“The writers and I all subscribe to the dramatic philosophy of playwright Chekhov, who said that if you establish a gun in Act 1, you better have it get fired at somebody by Act 3. We knew that ricin was still out there and we knew it was hidden behind the wall outlet in the old White house bedroom. I guess we could have let it slide, but we thought to ourselves, ‘The audience has been real good to us, they’ve paid very close attention, we want to reward them by not leaving any loose ends here.’ And also, honestly, the actress who plays Lydia [Laura Fraser] is a wonderful, warm, sweet person but the chatacter of Lydia — we were all champing at the bit to see her get her just desserts much more than Todd even. Todd is so likable, you almost have these ambivalent feelings when he’s being choked to death. But Lydia? We were all of one mind when we were saying, ‘Oh man, she’s got to go.’ So we figured, ‘What’s the best way to do that?’ And we thought somehow she could be there when the M60 goes off, but then we thought, ‘She’d never be around for that kind of stuff.’ She’s just not that person. And then we thought, ‘Can we use the ricin?’ So we were very proud of ourselves when we figured out a way to hang it all together and have her get her just desserts as well. It was very hard-fought, trying to figure out how to plot all this stuff out so that everyone got theirs. Everyone had their final moment in the episode, and it caused a lot of headaches and a lot of stress trying to get all the stuff worked into the final hour of TV [laughs], but I feel real good about it that we did it.”
On the most challenging scene in the finale to pull off
“Oddly enough, the revenge stuff at the end is — this is an odd way to put it because it’s so violent — but that’s sort of the cherry-on-top stuff, that’s the stuff that the audience needs to see for their own emotional contentment. At the end of the hour, the audience needs to see Walt get revenge against the guys who killed Hank. That’s sort of a necessity, and that stuff was a little more clear-cut. But the most important sequence in the episode for me probably was Walt succeeding at his 62-episode long task, which is leaving money to his family. The sequence with Gretchen and Elliott at their house was the hardest thing of all for the writers and I to figure out. In the previous episode, Saul Goodman (Bob Odenkirk) lays it out for Walt. He gives Walt all the reasons why it’s impossible to leave millions and millions of dollars to his family. He says, ‘You’ll never get it past the cops, and if somehow you manage to get to your family, the cops will find out about it and they’ll seize it because it’s drug money. And if miracle of miracles, you manage to get it past the cops, your family is not going to take it because it’s from you and they hate you. Especially your son, who is primarily the one you’re doing this for, so it’s an impossibility.’ We kept talking about that in the writers room saying, ‘Jesus, Saul’s right on the money, no pun intended. There’s no way for Walt to do this.’ The Gretchen and Elliott scheme is structurally the most important sequence in the episode, when Walt pulls that scam on Gretchen and Elliott and he intimidates them into giving his family money so that it’ll ride past the DEA without the DEA knowing it’s drug money and then it’ll be accepted by Skyler and Walt Jr. as largesse, as charity and not as money from their patriarch. As soon as we figured that out, we were like, ‘Oh my god, let’s go to lunch!’ [Laughs] That’s probably structurally the most important moment of the episode, and the toughest one to crack.”
On how he feels now about ending the show just as it was surging in popularity
“Every story has its running time, and it’s just hard in television to know what that running length should amount to, and I feel very happy and satisfied by the fact that we’re wrapping up now. I can’t even believe that the ratings have increased with each episode — I just think it’s wonderful — and people have asked me, ‘Does it make you want to go on and do a bunch more episodes now?’ Just the opposite. It makes me think, through quite a bit of good luck being involved, we really did pick the right moment to exit the stage, and I feel even more confident of that now than I did before.”
http://insidetv.ew.com/2013/09/30/breaking-bad-finale-vince-gilligan/