Jennifer Carpente and Michael C. Hall

After eight seasons, over 100 kills and more blood than we can imagine, Dexter will sign off for good on Sunday.

From the beginning, Dexter Morgan (Michael C. Hall) was a serial killer incapable of having emotions or a true human connection. But over the course of eight seasons, he's faced love, loss, heartache and even friendship with his foul-mouthed sister Deb (Jennifer Carpenter), proving that he may have the capacity for feelings. Will that be Dexter's downfall in the series finale? We'll find out Sunday (9/8c, Showtime). Before then, however, Hall and Carpenter look back at eight seasons of kills and thrills:

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What initially attracted you to Dexter?

Michael C. Hall: I think the audacity of the submission to invite people to identify with a serial killer. It felt like a crazy proposition, but one that if we could pull it off would be very exciting. Obviously the show is constructed in such a way that characters are presented in such a way that the audience is given permission to identify with him. Initially that was the appeal. It evolved quite a ways beyond that, and the character finds himself in a place at the end of the series that I couldn't even imagine when we started.

Jennifer Carpenter: The script was like a Mack Truck. You just couldn't miss it. It just swept you up and it was invigorating and unlike anything I'd ever read before or have seen on television. The other thing that attracted me to it was employment. Before that I had been waiting tables and I did a comedy [White Chicks] with the Wayans brothers and then I had no idea what was going to happen. I had done Emily Rose too but I don't really like to be unemployed. I'm my father's daughter, and he worked at a factory my whole life, so there's something very satisfying about showing up to a job. The opportunity for employment was very attractive.

What was it about Dexter Morgan that made him a likable and relatable character?

Hall: Certainly the fact that he kills the kinds of victims he kills and that he doesn't just off people who look at him funny gives people permission to identify with him. He was compelling because he made the claim that he was without the capacity for human emotion and we were maybe meant to be suspicious of that. Even we thought he didn't have the full capacity, in spite of anything, he did seem to have the appetite; an appetite that was exploited by the Ice Truck killer (Christian Camargo). Over the course of the show, that appetite has been exploited again and again in different, deeper and dicier ways.

What depths did you have to go to in order to play a serial killer?

Hall: I'm someone who certainly is not opposed to doing a certain amount of research and certainly I'm interested in drawing in my own experience up to a point. But I do think that some of the appeal with Dexter is that it inevitably requires an imaginative leap unless I was willing to go out and actually off people and see what that felt like. I wasn't going to be able to know exactly what it was like to live his specific life. Frankly, if I did that it wouldn't really help much because it's not really my inclination. I have my compulsions, but it's definitely not that.

How much did you relate to your character?

Carpenter: From the beginning, I wouldn't say we were the same shape, really. We couldn't have been mistaken for each other, but I was as green as she was. When you're doing television, there's not a set date for it to end or a set story so you know exactly where you're taking it. I had to lend her pieces of me to survive and keep it honest in a way. I had to use my imagination to make her very separate and far from me as well. So it just became about isolating between one side or the other. Either I was working at something for myself or I was taking a vacation from myself and really luxuriating in this fictitious person.

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Talk about the evolution of Dexter and Debra.

Carpenter: When I look back on it, I'm aware that it wasn't easy. It wasn't a job where I was ever at rest. Creatively, I'm really grateful to that. But it wasn't like she made a pivot from season to season. It was like she was spinning in 360-degree circles again and again and she just couldn't find a place to stop. There was a part of me, just as the actor, that envied the voiceover. I wish Deb had one from time to time because I had no idea what to make of it. With the clock running and someone is going to say, "Action" momentarily, you have to just pull the trigger and make a decision. Often times that's what I was doing. I got to a place where I started to work with what really was in the room with me and often times that was fear and confusion and muscle. And often times I feel like those are also adjectives that can be used to describe Debra. There was something, by the end of it, something that was pure in the beginning, unfortunately became spoiled. I feel like I knew four seasons in that there was never going to be a happy ending for Deb.

Hall: Over the course of the show, it's been about navigating the twists and turns in ways in which he has evolved or devolved. Playing the role has ultimately required a great deal of flexibility in terms of my initial conceptions and how those have been challenged and how they've had to morph over the life of the show.

Was there a line you personally wouldn't cross on the series?

Carpenter: When the conversation about Debra having feelings for her brother came up, there was talk about a scene where — you know the scene where they're having Chinese food and they kiss? That was originally going to be a love scene, and I absolutely was not going to do that, so that's the first thing that comes to mind. I renegotiated it down to a very swift kiss.

Hall: For me, any kind of line drawing was more about how we did things. Sometimes we were missing something in terms of the connective tissue that I felt we needed to feel like we were maintaining some sense, or my own sense, of the character's truth. I always had as much of an appetite as anyone for him to go far and farther, to completely go unhinged and fly off the handle. But because we didn't want to just blow the things up or crash and burn, we had to have him maintain some sense of control over his world and himself.

What has been your favorite moment on the series?

Hall: There have been so many, but I always come back to Dexter discovering his origin story and doing that face plant into the room full of blood in the 10th episode of the first season. There was something about playing that scene and setting up all the cameras, we could only do it once because we were making such a mess.

Carpenter: There were a lot of scenes that I was afraid to play, like when Lundy (Keith Carradine) died in the parking lot scene, I was a mess. I didn't want to do that. I didn't want to play that scene. I didn't want to shoot LaGuerta (Lauren Velez). It was traumatic in a weird way. You're so far into the series, it becomes real to a certain extent. It hurt me personally to play those scenes. But they are, in turn, my favorites because with great risk comes rewards. They taught me so much about how important it is to work with good people.

One of the most revealing scenes that I've played was with Quinn (Desmond Harrington) in the finale. We have a scene in the ambulance and it was the scene that left him for the series. As soon as we cut on it and it was over, it was as if the love that existed between these two characters was hovering between us and they could both see it, and it broke my heart. Because I don't know that I'll ever work with another actor that will go there the way that Desmond did. Basically what I'm saying is I'm spoiled rotten. I guess every moment was my favorite because I feel like there were so many other actors that just didn't feel like getting out of bed to go to that audition that day and then I had a good day. The course of my life and this show could be very different.

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Who has been your favorite villain?

Carpenter: John Lithgow, because he was a teddy bear to be around and a grizzly to work with.

Hall: Trinity (Lithgow), because he is the most complex, formidable and the most like Dexter in terms of the way he tried to live his life. And he's my favorite dramatically because the real marker is before and after Trinity kills Rita (Julie Benz). Before that point, Dexter could really operate under the reasonable assumption that he was not affecting those closest to him with what he was doing. Ever since, he's been scrambling to protect people from who he is.

Who has been your favorite kill?

Hall: My favorite kill is the one that I'm doing at the moment — that's what Dexter would say. I always go back to Little Chino (Matthew Willig) because he was so damn big. Pretending that I could vanquish such a beef bus, as Deb calls him, was a pretty heady thing.

What was your favorite Deb curse word?

Carpenter: It's kind of strange that you're asking me this question now because I'm sort of repulsed by all of it. At the gym this morning, Robin Thicke's song came on and someone mentioned it's possibly about date rape or something. It's called "Blurred Lines" and they repeat, "You know you want it," again and again. That's so much of what's out there right now on the radio and television. It's just crude and disgusting and it infuriates me, to be honest. I have to justify it with Deb because it's her go-to tool and it was effective and it made people pay attention to her. It was a crutch really. It wasn't cheap, I guess is what I'm saying. So to go back and say "I loved it when she said this F-bomb or this weird compound blending of two bad words" makes it cheap and I would like to leave it thinking that it wasn't.

Dexter had several love interests over the years, including Rita, Lila (Jaime Murray), Lumen (Julia Stiles) and Hannah (Yvonne Strahovski). Who do you feel was the most right for him?

Hall: I would say Hannah, as much as her acceptance of Dexter's whole person was not in any way begrudging, or utilitarian, or fetishistic, she just accepted it. And she accepted it within the context of someone she believed to be and insisted was a broader person. I think that is a part of why Dexter is himself and open to that notion in a way he hasn't been before.

What was the turning point of the series?

Hall: [The Ice Truck killer and Rita's death] are fundamental early on. His discovery of his nature of his origins story, and that he's not alone, and that he has this brother, and that he has an appetite for a connection with him, and this may be trumped by his sense of connection with is sister: Those are all things when we meet Dexter at the beginning of the season he doesn't anticipate and isn't aware he has the capability to experience or appreciate.

Certainly when Rita is killed — someone else in Dexter's world, a world that is being more and more characterized by seemingly legitimate connection, this is his wife with whom he has a child — someone else is implicated and whatever compartmentalization he had successfully cultivated starts to fall apart and those lines start to blur or disappear. Dexter's reeling from that throughout the rest of the series. Every season and every major relationship that Dexter has further exploits that there's a real appetite for connection and revelation. And in a way, the more he moves towards the light, the more the darkness is all the darker in stark relief. The more he becomes like a human, the darker it is to really consider the fact that he continues to kill.

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What is your reaction when fans say that Season 4 was the height of the series?

Hall: I mean I get it. Like I said, he's just been reeling ever since Trinity got the best of him. He killed Trinity, so I guess he got the best of Trinity in a way, but he killed him with a lack of knowledge of what Trinity had really done. As the show initially presented some big adversary, Dexter would one way or another come to know and vanquish, that's the pinnacle of that model. The Trinity killing was the most prolific, formidable foe that Dexter ever faced.

Carpenter: What's funny is that maybe ignorance truly is bliss, because I really did somehow manage to be ignorant to the success of the show. Even when people say something to me now, I'm sort of skeptical, like, "Who told you about the show?" I can't imagine that people are actually watching it. So, was that the height of it? I don't know. I don't really give a lot of credit to people who make comments on the internet. I avoid it really. That's their business. If people think that was the height, then they're right because whatever the fans say goes.

If that was the high point of the series, what was the low point?

Hall: It's hard to be objective even as a viewer. I see it all as a whole when I see different seasons that might have been more frustrating to watch as the overall evolution of the character. There have definitely been moments that have been more challenging to wrap my head around than others.

Is there anything you would have changed?

Hall: I might have had him kill Trinity's son (Brandon Eaton) when he went to Nebraska in the 6th season when the Ice Truck killer comes back and finds out the kid just has daddy issues and doesn't kill him. I thought he should have killed him anyway.

How do you feel about the final season going back to the beginning and looking at how the code was created?

Hall: I was never very interested in the show staying in the same place. Dexter could have gone more strict, hard and fast adherent to the code and we could have followed a similar formula and had a sort of "Who's Dexter going to kill this week?" be the primary question we were preoccupied with. But there was a desire to directly challenge the audience's affection for the character. Dexter is someone who had the code instilled in him by a father (James Remar) who arguably was a great dad, outside-of-the-box thinker, and on the other hand, abusive. Dexter has an impulse to rebel and his roles are not conventional roles. They're roles imposed by a self-appointed deity in the form of his father and, he comes to discover in the final season, in his spiritual mother (Charlotte Rampling). If he's going to rebel, he's going to rebel against the code and play faster and looser with his roles. He always, in the end, comes back to an appreciation for how it's protected him and kept him safe. But we don't always learn our lessons on time. Sometimes we learn them too late.

Carpenter: Most years I was given the bare bones before we shot the first episode of each season. This year, I was told about what the first three episodes would look like. And the way that it was presented to me is that the rest is all up in the air. The rest was Dexter's business. So I didn't know and I didn't have Showtime because of the Time Warner thing. I turned it off. So I'm lost. I remember it as someone who lived it and not someone who studied it. I've never been confused about a season, but I'm confused about the end, and I think that might be a big sign for it being successful if that makes any sense.

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How do you feel about the end of the series?

Hall: I feel good about it. I feel like it may well be polarizing. I think it will be a broad spectrum in terms of the response to how the show ends.

Carpenter: I'm really satisfied. All I can hope for was something that felt legitimate with her. I feel like there are so many times when, for the sake of momentum in the stories, I've had to do things that went against my philosophies about Deb. The things I need to be true about her. This isn't for the sake of the continuation of the excellent writing that we had. But the end all felt very organic and natural and honest. When I found out how her story was going to wrap up, I knew that they were discussing three separate paths for it to take, and I was champing for a path that wasn't taken.

What are you hoping the audience will take away from the series?

Hall: A sense that they've taken a ride that has been consistently compelling and cohesive and has started in one place and ended somewhere else. Different people like the show for different reasons. I just hope it's something that continually resulted in people leaning forward. I think it's done that.

Carpenter: It's a funny thing because it was the most amazing show. I feel like we are all huffing and puffing at the finish line. I feel like we all survived a marathon together. It's a strange thing to say to the audience, "We ran for you. I hope you know we worked so hard for you." So I hope they know that, although there may have been highs or lows throughout all eight seasons, which is something to be expected for something that goes that long, I hope they know it was sincere. I hope they know it was emotionally expensive for all of us. In a weird way, this could be totally off the mark, but I feel like Dexter, the series, sort of raised the bar for what cable television writing and storytelling could look like. I'm going to go ahead and believe that's true and I'm going to go ahead and be proud to have been a part of it. I hope they have better TV for it.

How do you feel about saying goodbye to the character?

Hall: I feel good about it. If you play a character long enough as an actor, your sense of acting and your sense of playing that specific character become fused in a way that it's sort of a mind bender so I'm glad to sort of disengage from this particular guy and move on to other things.

Will you be able to move on from Dexter?

The series finale airs Sunday at 9/8c on Showtime.

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