"It seemed like the right thing to do at the right time," the executive producer and creator of the comic series tells THR of the decision to kill off a central character in the season three finale.

[Warning: This story contains major spoilers from The Walking Dead's season three finale.]

AMC's The Walking Dead took a massive detour from the comics on which the series is based during Sunday's third season finale when one of the original stars was shockingly killed off.

During the episode, Andrea's (Laurie Holden) efforts to bring peace between Rick's group and the Governor-controlled Woodbury ended when Milton -- who turned after being stabbed in the stomach -- took a bite of her neck. With Michonne by her side, Andrea used Rick's gun to take her own life before reanimating as the undead.

Andrea's death marked a major detour from the comic series -- where Andrea has evolved into Rick's second in command and a love interest. The Hollywood Reporter caught up with executive producer Robert Kirkman, on whose comics the series is based, to discuss the decision to kill Andrea, keep the Governor around for season four and if the series -- which killed off its two leading ladies this season -- has a problem with women.

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The Hollywood Reporter: Walk us through the decision to kill Andrea. It's such a huge departure from the comics.

Robert Kirkman: It's a big departure from the comics, which to a certain extent is somewhat risky but at the end of the day I like the idea of there being big differences that key in to this is the show, this is the comic. I like that there's some kind of separation there. It was definitely something that weighted upon us heavily. The unfortunate thing is that you're not really going to see why this was a good decision and good for the show until season four. We thought having that tragic end to her story line -- having [Andrea] work so hard to save these people of Woodbury and find a peaceful resolution to this conflict was really something worthy of the character. It's also something that changes Rick's (Andrew Lincoln) mindset and alters a lot of the characters and their modes of operation moving into the fourth season. It seemed like the right thing to do at the right time.

THR: Who first suggested doing it and when it first came up in the writers' room, was it an easy decision?

Kirkman: It was something [departing showrunner] Glen Mazzara introduced in the writing of the last few episodes. It's something that was debated quite a bit. There was a lot of opposition in the writers' room. I bounced back and forth between "We really shouldn’t kill her" and "this is a good idea." In the end it all came together and we decided to go for it. It was definitely something that divided the room to a certain extent.

THR: On The Walking Dead, we know that anyone can go at any time. Why was it Andrea's time? What is the message you're sending in killing off this character?

Kirkman: Aside from reaffirming the unsafe nature of the show, it's a bleak show and the message we're trying to send is Andrea would go to any length to save those people and she ended up sacrificing her life for them. Speaking to the character of Andrea, it was showing how devoted she can be and how things, despite all of her best intentions, went awry. We've got a lot of work to do with the Governor (David Morrissey) next season. Having him be that diabolical and sinister will serve his character moving forward and that was a pretty important and defining moment for him that will pay off in the fourth season.

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THR: Are you worried about backlash among the comics' core fan base?

Kirkman: There's always a risk of that and we'll see how things go. The comics still exist and I'd urge those people to continue reading the comics where Andrea is still alive. Just know the show is something different and we are telling different stories. It doesn't mean we're not going to see a lot of the big stories and big events from the comic book in the TV show eventually; it just means those things will be a little bit altered from time to time. Hopefully it will be exciting, new and fresh just like it was the first time you read the comic, which is really the goal.

THR: Was it always the plan to have Andrea die? We've heard that in the original season three plans Andrea survives and as the leader of Woodbury, opens the gates to everyone.

Kirkman: That was something that was definitely pitched. I'm not going to say we came in on Day 1 of this season with this, but it was decided well before the end.

THR: In a behind the scenes video, Andrea's fate seems very different -- where she's chained to the chair and unable to free herself and Milton attacks her. How much did the finale change?

Kirkman: Things change in editing room quite a bit as the process goes. There were some alternate scenes shot but that's not uncommon and has happened a few times on the show. I'm unaware of the scene you're talking about, I didn't know AMC had released something like that.

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THR: The entire season was leading up to this big battle between Rick and the Governor, which we never really see and the Governor effectively walks away after murdering most of his army. Why take the story in that direction?

Kirkman: We've definitely got more story to tell with that guy. I always liked the idea of seeing him again and not having a clear resolution to that conflict. Rick and the group are still at the prison and the Governor is still out there. There's more ground to mine. Knowing the Governor isn't dead is going to weigh on these characters when we come back in season four and we'll have to see where things go.

THR: Just as we were starting to see Merle changing and scenes exploring his relationship with Daryl (Norman Reedus), he's killed off in the penultimate episode. Why was it necessary to kill Merle?

Kirkman: It's important to note that running out of story isn't a reason to kill a character. Having more story to mine isn't a reason to keep a character alive; it's what story comes out of it and how does the story change with death. Daryl Dixon has become a very important character in the show and his character had changed and evolved in very interesting ways over the course of the first three seasons. Having Merle back was always planned to be somewhat temporary thing. We wanted to see how Merle's return would affect that character and seeing Daryl revert to past behavior -- to bad behavior -- was something we really wanted to explore. But in the end, Daryl had moved past that character and we wanted to get back to him not having that brother altering his behavior moving forward or influencing him in any way. Merle's death was really about activating Daryl in an interesting way that will pay off in season four.

THR: The show's two leading female characters (Holden's Andrea and Sarah Wayne Callies' Lori) were killed this season and the series has been accused of having a problem with women. Why kill off these two in one season?

Kirkman: Both those decisions were made independently and certainly wasn't an effort to get rid of our two leading females in one season. Lori's death was set up in the comics and planned for a long time. As the story of Woodbury started taking twists and turns, Andrea's death made the most sense. We've introduced a lot of other female characters along the way: Michonne (Danai Gurira), Maggie (Lauren Cohan) has taken a more central role and we've got Sasha (Sonequa Martin-Green) -- Tyreese's sister. Coming into season four, I can say with absolute confidence that there's no lack of female characters. Female characters will take central role in season four. It's about the evolution of the show; characters are going to come in and go and the cast is always going to be changing but it's still going to be The Walking Dead at the end of the day.

THR: How will season four be different with the Governor still out there and Rick now at the prison -- with a larger group?

Kirkman: It's going to be different in a lot of ways. We'll see a very different Rick Grimes for one. His experiences against the Governor and with the various things that happened to him in season three are informing his character in huge ways. We'll see a lot of familiar elements from season three: we'll see the prison, Rick and his group are still in the same place but those elements are all going to be radically different. I can't really get into it but season four is going to be extremely different than season three in some very startling and cool ways.

THR: Milton also failed to survive the season but in the finale never had the moment where he accepted that once you turn, your humanity is gone. What was the point of exploring that story?

Kirkman: We always like to give little hints as to what may be going on in this world; there's not a central mystery to the show -- there's not who caused the zombies, how are we going to stop this; that's not what the show focuses on -- but it's still fun to have characters in the mix who are trying to discover this world and learn more about what's going on and Milton served that purpose much like the CDC and Dr. Jenner did in season one. There might be some hints in that story line that will come up later, I can't really say, but there's definitively some important moments in there.

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THR: Rick tells Carl "They're with us." What's his message to Carl, especially after he learns that his son gunned someone down in cold blood?

Kirkman: Because of Andrea's sacrifice and seeing the Governor for who he is and knowing he's killed all these people, Rick is changing. This is the moment where Rick takes a turn; he's no longer going to be pushing people away, he's no longer going to be doing what ever he can to protect these people in ways that hurt other people. He's not going to be the guy who would leave that guy on the side of the road -- the backpack guy in Episode 12. He's letting the people of Woodbury in and tying to tell Carl that these people are like us, you have to be open to this and the only way to survive in this world is to have people and be in a community. That's going to be a big part of season four.

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THR: Glen Mazzara departed the series, citing creative differences, with production shut down multiple times and scenes from the finale reshot. How much did the decision to replace showrunners have to do with the decision to kill Andrea?

Kirkman: You'd have to talk to Glen and AMC about all that. I can't really comment.

What did you think of Andrea's death? Hit the comments with your thoughts below. The Walking Dead returns in October on AMC.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit