Peter Gould tells THR the show's penultimate episode is all about "the consequences of what's happened so far," adding: "if we can get people to root for Walt [again]...that would really be an accomplishment."

Warning: Spoilers ahead for Sunday's episode of Breaking Bad, "Granite State."

Breaking Bad unleashed an intentionally slower-paced and undeniably devastating penultimate episode Sunday.

"Granite State" saw both Walt (Bryan Cranston) and Jesse (Aaron Paul) at arguably their lowest moments in the series and featured a standout guest performance from Robert Forster as the oft-mentioned but never seen "disappearer."

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"After the volcanic events of the last episode, you don’t want to keep the pedal on the gas continuously. You need to mix up, you need to mix up rhythms," longtime Breaking Bad writer Peter Gould tells The Hollywood Reporter.

Gould, who wrote and directed the episode, says he and creator Vince Gilligan knew they needed "a powerhouse actor" for the role of the disappearer and in the writer's room had used Forster's performance as straight-shooting bail bondsman Max Cherry in Quentin Tarantino's Jackie Brown as a model.

"He brings with him an air that tells you so much about the character," Gould says.

Gould notes that in last week's "Ozymandias," Walt is at the height of his evil, while here he's a diminished man. He says he and the writers hoped to get the audience back on Walt's side.

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"As we were working on it, we said, 'Gee, if we can get people to root for Walt or take Walt's side, that would really be an accomplishment,' " Gould says. "[Walt's at] this dead end, where nothing he does makes any difference. When a character suffers in a way that feels real, it's very hard to not to feel a little bit of empathy sometimes."

Find THR's full conversation below, where Gould discusses the "heartbreaking" work that went into Andrea (Emily Rios)'s death, how Charlie Rose ended up on the show, and why Cranston had to completely reshoot his terribly sad phone conversation with Walt Jr. (R.J. Mitte).

How did you cast Robert Forster as the disappearer?

When we were talking about the character in the writer's room, we literally called him Robert Forster. Our reference to the part was Max Cherry from Jackie Brown. Then, lo and behold, when our casting people reached out to him, he was willing to do it. Vince and I got on a phone call with him and told him about the part and he was willing to rearrange his schedule. It was really a thrill. He brings with him an air that tells you so much about the character. He plays such a huge role in the episode, so we really needed a powerhouse actor to put next to Bryan Cranston.

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He and Bryan had some heavy scenes together. How'd you make that work so well?

A lot of times, the best directing is the least directing. You try to see what the performer is doing. Robert did tell me I gave him advice he hadn't heard before, which is a great compliment. I told him, "You can take your time. If it feels good to go slow, then go slow." A lot of times, directors are rushing through scenes, with good reason -- you're trying keep the story exciting. I felt there was a certain rhythm that was called for that was maybe just a little bit slower, letting the moments sink in. He took that and made it into something that worked for him. He was brilliant, and I was very grateful.

Walt and Jesse are both essentially powerless and stuck in this episode. Is that fun to play with as a writer, or is it more challenging?

It was both. After the volcanic events of the last episode, you don’t want to keep the pedal on the gas continuously. You need to mix up, you need to mix up rhythms. A piece of music that's always going at the same speed isn't as effective or emotional. This was a very special episode because this was really about the consequences of what's happened so far. That's one of the things that's special about Breaking Bad. It's not just about action. It's about the consequences.

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And Aaron Paul gave an amazing performance.

Aaron Paul turns in just an unbelievable performance and has probably half a page of dialogue at most. He probably never says more than four words in a row. To me that's really kind of exciting. The last episode I directed had Aaron in drug rehab in 407, "Problem Dog." He had that amazing speech about shooting Gale in a story about a dog. It was such an amazing job with that dialogue. It was such an intense moment. And here I was getting to work with him and it was all physical. It was all about what he was doing with his eyes.

Andrea's death wasn't explicit, but it was very disturbing because of Jesse's reaction. What did you write in the script, and what did you tell Aaron to do there?

I wrote that it was an explosive reaction. With directing, I want to see what the actors bring to it first before I start messing with it. The great thing about having creative, brilliant actors like Aaron Paul is that they feel deeply. Aaron spends a lot of time with his script. He spends a lot of time thinking about where his character is and where his character is going to be. He analyzes the script, as does Bryan. His reaction was so explosive and heartbreaking that I was all about getting it on film. Originally in that sequence, there was a little bit more with him at the beginning. There was a piece where he was watching Todd approach Andrea's house. We found his reaction was so strong and so powerful that we wanted to save it until just before the shooting.

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Over the years, you and the writers have killed a lot of characters. What does Andrea's death mean to you? Is it just another day at work, or does it take it out of you?

It was really kind of heartbreaking. It was not a technically complex scene, but emotionally it took it out of everybody. I'm always a little bit surprised at the power of these things. One of the choices we made this season was not to wallow in the physical effects. When Hank was shot, we cut wide. It wasn't like when the cousins got shot and there was a piece of skull in the camera. These things are as much about the consequences as about the actions themselves.

This was a breakout episode for Todd. He seems to have a fondness for Mrs. White and Jesse. But he doesn't really care if he has to brutalize them.

Todd's missing a piece. I think he genuinely likes Jesse. He genuinely respects Skyler, but he's going to do what he's going do. In a weird way, he's the guy Walt thought he wanted Jesse to be way back when, when he wanted Jesse to go get their money [that was stolen from Skinny Pete] and "do what's necessary." Jesse Plemons is a very creative, smart actor who works very, very hard. He had some real inspiration. One of my favorite moments was in this first scene in the episode where they're watching the tape of Jesse talking about Drew Sharp's death. Jesse calls Todd a "dead-eyed Opie peace of shit." I look over at what Jesse Plemons is doing and he's chewing this food and giving a little smile. It's like he's thinking, "I like Jesse. Jesse remembered my name." The rage doesn't touch him.

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At some point in the series, pretty much every viewer finds they are no longer rooting for Walt. In this episode, we're rooting for Walt again because we hate the Aryan gang so much. Was that a goal?

As we were working on it, we said, "Gee, if we can get people to root for Walt or take Walt's side, that would really be an accomplishment." In the previous episode, you have Walt being as villainous and evil as we've ever seen him. In this episode he reaches the end of that. He enters into this frozen hell, this dead end where nothing he does makes any difference. When a character suffers in a way that feels real, it's very hard to not to feel a little bit of empathy sometimes.

To add to Walt's woes, the Walt Jr. conversation didn't go the way he wanted. What was that scene like to create?

It was an incredibly painful scene to write as a father, to write that begging. He's begging for some little sliver of meaning in his life. Breaking Bad shoots on film, and that scene with Bryan on the phone is a big scene. R.J. Mitte came to the set to be off camera with him. It was beautiful. Then we sent the film to Los Angeles and an airplane ran over it. We still have the crushed cans. Bryan had to get back into that makeup, and he had to get his head back into that and do that whole damn scene all over again.

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That scene would be difficult to do once, much less twice.

All the dads on the set were getting misty-eyed over it. The father-son relationship has been an emotional touchstone on the show for me since the beginning. When my daughter was born, my career was really at a standstill. Boy, I would've been tempted to cook meth (laughs). I identified with Walt from the beginning for sure.

How do you read the scene with Gretchen and Elliott? Does Walt simply hate not getting credit for his work at Gray Matter?

It's hard to talk about because it leads into the next episode. There's no question seeing Gretchen and Elliot waved a red flag in front of Walt. What he's actually thinking there, you can make a lot of assumptions. It'll be really interesting to talk about after everyone's seen the finale. I think people are going to see it in a different light.

How did the Charlie Rose scene work?

It's the only episode in Breaking Bad not shot in New Mexico. That was shot after the show wrapped. My daughter and I flew to New York, and we shot that scene with Charlie's crew, in his studio. That was the last thing I shot on the episode.

What can you tell us about the spinoff series, Better Call Saul? Has a city been picked? Is there a chance we'll see old characters such as Mike?

Everything is still up for grabs. We have a lot of ideas. I'm really excited about working with Bob and with Vince Gilligan again. I love the character. There's so much more to say about Saul Goodman. But it's not a done deal. We still have a lot of work ahead of us to figure it out.