The EP tells THR about the choices made leading up to the finale, what castmembers to expect back when the series returns and how it feels to rip off the Band-Aid: "We're in the enviable but terrifying position of starting again."

[Warning: Spoilers ahead from Sunday's season-three finale, "The Star"]

Just three seasons into its run, Homeland is on the verge of a complete reset. Sunday's finale settled the long-lingering question of whether or not the Showtime series could continue to sustain Nicholas Brody -- the marine, terrorist, congressman, informant, fugitive and eventual hero played by Emmy winner Damian Lewis.

Brody, of course, is now out of the picture. The episode settled that at the halfway point, when the CIA went against Carrie (Claire Danes) and Saul's (Mandy Patinkin) wishes and sold Brody out to the Iranian Revolutionary Guard. Brody was quickly tried and hanged, dangling before a sobbing Carrie and a packed square of Iranians screaming for his blood.

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The move sets up Homeland's fourth season to be a complete departure from the series up until this point. And while most of those details are either a work in progress or not ready for public comment in the immediate aftermath of the finale, Homeland executive producer and showrunner Alex Gansa spoke with The Hollywood Reporter about the dramatic events, why things played out the way they did, and what viewers can expect next.

At what point did you know this episode would be the end point for Brody?

It was one of the very first decisions that was made in the story room this season. Sometime in January, we started to talk about this being the season that Brody would not survive -- but the manner and the exact method of his death were things that we did not decide until sometime in September. We knew his shelf life had expired but didn't know exactly how [his death] would take place.

Was there any part of you that considered keeping him on for the fourth season?

That idea was definitely on the table at the beginning. We really spent a lot of time talking about what a great deal of emotional territory we had covered -- not only with Brody but between Brody and Carrie. There just wasn't all that much left to explore. I think if you look at Brody's limited appearances this season, it also speaks to that same problem. When Brody was onstage and on camera, we wanted it to be for a compelling and powerful reason and not just for the sake of him being there. We got him onstage when we needed him, and obviously as the season drew to an end, he became more and more prominent because we were ultimately moving to the point where he would lose his life.

Did those episodes without Brody give you more confidence to tackle the show without him?

It was kind of a test case. We did a bunch of episodes without him. It gave us an opportunity to bring some new people onstage, people who had short shrift the first and second seasons. And we introduced a lot of new characters like Senator Lockhart. Tracy Letts' performance, I think it's just spectacular, and the same for Naz [Nazanin Boniadi], who plays Fara. These are characters we got to explore and enrich and see whether or not the show can withstand Brody's absence. Honestly, I think it has. I think they raised their game and made the show vital without that central character onstage.

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What do you say to the viewers who don't see last night's episode as a definitive death?

I think it's going to be hard to spiritually kill Brody forever. Carrie has his child, his little daughter, so Brody will be alive that way. But everybody should rest assured that physically he will not be resurrected -- although the specter of Tony Almeida haunts the show a little bit. He was strangely resurrected in the last season of 24. Honestly, you can ride me out of town on a rail if that happens. You have my permission.

How did you settle on the idea of this public execution rather than something more sudden?

It felt to us as if Brody, once he was in Tehran, it would have felt preposterous for him to escape after committing this murder of Akbari. And it was clearly in Javadi's best interest to catch him and execute him as quickly as possible. Brody is an unstable and changeable person. Javadi knows that the safest place for him to be is six feet under. That's how they execute people in Iran. They put a rope around their necks and they string them up. It's a very public, humiliating, sadistic and crazy blood sport that goes on there. Putting Carrie in that audience felt like the right element. It gave the death a public spectacle quality, which we felt was important.

In an interview, Damian referred to Brody as "a monster that [the writers] couldn’t quite control." Did it ever feel that way to you?

I think Doctor Graham spoke it plainly to Brody in the third episode of this season: Brody is a cockroach. There is no doubt that his character, from the very beginning, has been a challenging one to write. He's the most opaque and changeable and he's so damaged. This guy spent eight years in captivity, many of those being tortured. It's difficult to get inside that guy's head. He's always been something of an enigma. That's what made him so difficult to play and so tough to cast. We're so lucky to have gotten Damian Lewis to play that guy. I don't know many actors who could have played him with that kind of complexity and depth and also maintained that unknowability. You didn't know up until the very end what was going on in his mind, and that's really difficult. I know Damian faced that challenge every day, but whether he was out of control, I think he had a fairly good hold on [Brody]. We talked very seriously about killing him in season two, but ultimately I'm just glad we kept him alive because we wouldn't have had this season and we wouldn't have gotten to play some of those moments.

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You've said that you wrapped the second season with a lot of indecision about three. Where are you at right now?

We're definitely waiting to regroup until the new year. If we had a few ideas at the beginning of season three, we have fewer at the beginning of season four. The show is really going to have to undergo a serious reboot and reinvention. If there's one idea that we're floating around that feels like we could get some purchase on, it's the idea of seeing Carrie do what she was trained to do -- and that is being a case officer in a foreign country. That feels like an interesting place to begin. But beyond that, we're in the enviable but terrifying position of starting again.

Is that more liberating or intimidating?

I think it's liberating -- I hope it is. We'll know in the first month of sitting around and talking. Our actors are fantastic. We have Claire, Mandy, Naz, Rupert [Friend], Tracy and F. Murray [Abraham]. We're not starting from scratch, but the show is going to be different. It's exciting and terrifying.

And you still have Mandy, yes? You left that a little open-ended.

I've got to put everyone's minds to rest about Mandy. The fact of the matter is that the character of Saul Berenson is now working for a private contractor. The CIA outsources so much work these days to these private contractors. Saul may not have a desk at Langley, but his operational interface with the CIA is going to be big.

Email: Michael.OConnell@THR.com

Twitter: @MikeyLikesTV