It's the beginning of the end.

When Dexter kicks off its final season (Sunday, June 30 at 9/8c on Showtime), expect a huge shift in the relationships we've come to know and love over the years. Sure, Deb (Jennifer Carpenter) and Dexter (Michael C. Hall) hit a rough patch last year after she discovered her foster brother is a serial killer, but they will hit their rockiest road yet in the wake of LaGuerta's (Lauren Velez) death.

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Season 8 picks up six months after Deb fatally shot her captain in order to protect Dexter, and she's not handling it very well. But Dexter will have more than his sister's downward spiral to deal with as the show introduces Dr. Evelyn Vogel (Charlotte Rampling), a psychiatrist who helped Harry (James Remar) create the Code that justifies Dexter's serial killing. She comes into his life when this season's big bad — dubbed The Brain Surgeon — sets his sights on her. Pair that with Dexter's angry ex Hannah McKay (Yvonne Strahovski) returning, and Dexter fans are sure in for one hell of a last hurrah this season. TVGuide.com turned to executive producer Sara Colleton to get the scoop on what's in store. 

It's the question on everyone's mind: Does Dexter have to die in the end?
Sara Colleton: I'm not trying to be evasive, but no matter how I answer, it will be indicative of where our thinking lies. Believe me, it's been a huge debate for eight years. We know what we've decided, but we've also had to accept that we can only please ourselves because no matter what we do, there will be people and critics who hate it, but we're doing what we feel is right for his series-long arc and what we want to say about Dexter, and by way of Dexter, about being a human being. We feel we have the right ending.

How long have you known this ending?
Colleton: It's been debated, but starting at the end of Season 6, we knew where we were going.

Do you know what the final scene will be?
Colleton: Yes, and now I close my mouth. [Laughs]

What would you say the theme of the final season is? Is it redemption? 
Colleton: Well, no. His search for redemption and atonement was Year 5 with Lumen and trying to make up for his guilt for not being there to protect Rita (Julie Benz) and trying to expiate his guilt through helping Lumen (Julia Stiles). He's always defined himself as a monster, but he's yearned to be human. In the last four years, you've really seen him evolve, but he's going to find out what the cost of being a human being is. It's not that easy. It's not that much fun. It comes with huge weight. He's going to be dealing with some of the aspects of that desire to be human that makes it so existentially despairing some days.

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It's been six months since LaGuerta's death. How is Deb dealing with the fallout?
Colleton: The one constant in Dexter's life has been his sister Deb, but her way of coping — she really has PTSD. She's in a spiral of denial. Drugs and alcohol blot it out and she refuses to have Dexter in her life, which is causing him to totally panic. She's just in total denial and feels that she has to punish herself. We always said that Season 7 was going to lead Deb on a dark and treacherous path, and indeed it has.

How is Dexter dealing with this changed relationship?
Colleton: He cannot function unless he has Deb in his life. She was the terra firma for him. He will do anything to get her back. Anything. It makes him sometimes act in a way that is more human than a cold-blooded, calculated sociopath that plots his every move. His feelings and his need for Deb have really made him behave in a very human way, so that makes him the most vulnerable than he's ever been in the history of the show.

Would Deb ever consider turning Dexter in?
Colleton: Well, now it's very complicated because she'd have to turn herself in, too. She's punishing herself in other ways.

What's the mood like at Miami Metro in the wake of LaGuerta's death?
Colleton: Six months have passed. LaGuerta was a good leader, but she was also ambitious in a way that sometimes she'd let her ambition get in the way of being a good, clean cop in terms of protecting her troops. Now Batista (David Zayas) has her job, so in some ways, it's much more of a cohesive group. Captain Matthews (Geoff Pierson) has come back on the force. He's now running the show and he's old school.

Showrunner Scott Buck told me we'd see Dexter examining why he kills this season and taking a look into his past. How will digging into his past inform his future? 
Colleton: It's not so much that he's digging into his past; he's just starting to realize that the same behavior hasn't gotten him what he wants. That's why someone like Dr. Vogel coming into his life is very influential this year.

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Dr. Evelyn Vogel helped define Harry's Code that keeps Dexter in check. How will she be part of Dexter's life this year?
Colleton: She's always thought of herself as Dexter's spiritual mother, and Dexter thinks of her as Frankenstein. She tells him something that allows him to feel really normal, which is that her whole theory is that sociopaths are a very, very important part of civilization and our society. They've always existed and always been the alpha males. Surgeons, politicians and financiers have very sociopathic personalities and that's what's allowed civilization to advance, so he should think of himself as normal and part of society. That's an interesting conversation for Dexter to start feeling less alone. "Well, if all these people can be successful without killing people..." It starts him on an interesting road of thinking. What's great about introducing Vogel this year is that she's the last remaining piece in the puzzle that is Dexter. It helps him unlock his thinking, but at the same time, he can't help but be seduced by her and not quite sure of what her motives are. He's very, very vulnerable this year because of his loss of Deb, so someone coming into your life and saying you're perfect at the most vulnerable time, he's pretty subjective to hear.

Is there ever a time when you could envision Dexter not being a serial killer?
Colleton: I don't know. If you put that in human terms about what we want and what we can't have, we'd all like to be something else.

Evelyn comes into his life because of the Brain Surgeon reaching out to her. How is this serial killer different than the other big bads we've seen over the years?
Colleton: He's not really coming after Dexter. Dexter is doing something for Vogel to help her, and it's also a Miami Metro crime scene. He starts being seduced by Vogel's charms and finding conversations that he has to have with her to help unlock things for him, so he does help her. 

Is Dexter's secret bound to come out this season?
Colleton: Anything is possible. I'm not trying to be cryptic, but what we've always tried to do, and what I hope our fans see with the ending they wanted or envisioned, that it'll be something that is the accumulation of what they have seen Dexter Morgan go through in the last eight years and his slow examination of the aspects of humanity and really thinking about who is he and what it is to be human.

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With Harrison growing older, will he start to realize what his father is?
Colleton: Harrison is still a young boy this season, but it's always been a huge fear of Dexter's; that genetically somehow he's passed on something to Harrison or he could be teaching him the wrong things. It's one of the things that makes him such a good father,dvd and movies, which is always one of the ironies of the show. He tries harder because he thinks about it. The odd thing about Dexter is that he really leads an examined life. He's constantly poking at himself.

What can you tell us about Hannah McKay returning to Dexter's life this season?
Colleton: She will come in and mix everything up,new dvd and blu ray releases. She's certainly not too happy with the way things happened last year.

Aside from Dexter's kills of the week, is there a chance other main characters could die in the final season? 
Colleton: That's one I can't address. We've really been able to do some nice stories for Quinn (Desmond Harrington), Bastista and Jamie (Aimee Garcia) and there's a wonderful story line for Masuka (C.S. Lee) this year, too, so we've really tried to highlight the characters that we've had for eight years that we've loved so much.

Will you have familiar faces from Dexter's past returning in the finale season, like Lumen? 
Colleton: Well, Hannah's coming back, but that's about it. Most of the other familiar faces he's disposed of. Hannah brings back a more interesting complication. With Lumen, the act that she needed of revenge, once done, was so burned out that she really couldn't go on with her life and wouldn't have need of Dexter, so it makes less sense for her to come, whereas Hannah has a few issues unresolved with Dexter.

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As you guys were planning the final season, did you take any tips from other antihero series?
Colleton: No, we really tried to shut it all out and not go on the internet and not hear what people are expecting or predicting. As I said, no matter what we do, it's going to be picked over. We realized all we can do is what we — who worked on the show from the inception — feel is the best possible ending and live with it because it can't please everyone. That's all you can do. So we've tried to ignore that kind of pressure that everyone seems to want to put on us.

Deb finding out Dexter's secret was a big milestone the show needed to hit. Are there other mile markers Dexter needs to hit before he says goodbye?
Colleton: The Deb relationship was a big thing and that's the cornerstone or the beginning of the end game. The other things are just things that would just come up because of the plot of the season in terms of the big emotional revelations and blowback. It's all Deb.

There seemed to be some spin-off talk, possibly with Deb or other characters. Has there been more talk about that?
Colleton: It confuses us so much because we hear this, or [the publicist] will come to us saying, "I heard today you're going to do a federal marshal who comes in." We just laugh. Right now, we are so focused on this show and it's been such a journey for all of us that we're all going to collectively and separately spend the month of August doing as little as possible.

How do you want to see Dexter end? Hit the comments.

Dexter returns Sunday, June 30 at 9/8c on Showtime.

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