'HTGAWM': Marsha Stephanie Blake on Playing 'Messy' Vivian Maddox and If She's Annalise's Killer (Exclusive)

The 'When They See Us' actress talks to ET about her juicy turn. Plus, watch an exclusive sneak peek from Thursday's episode.

Vivian Maddox has arrived and she's about to make Annalise Keating's life a little more difficult.

How to Get Away With Murder finally introduced Vivian (When They See Us' Marsha Stephanie Blake) in the flesh during last week's premiere, when she popped up at the end of the hour after arriving into town unannounced and dialing up her son, Gabriel (Rome Flynn), as she watched from afar. Vivian's re-emergence won't be without its complications -- the show does have Murder in its title, after all -- since Annalise (Viola Davis) and Vivian have shared history with the late Sam Keating, and Vivian's own relationship with her son is about to get even messier. 

When Blake was given an offer to join the ABC series for its final season, the actress had no clue who she was playing or how she fit into the picture. But after some prodding, she was sent a few scenes from the casting office that immediately gripped her. A self-proclaimed fan of How to Get Away With Murder, Blake shot off an email back to the casting department the second she devoured the material. "'Oh my god! This is amazing!!!' Exclamation point, exclamation point. Freaking out, fangirling out," Blake said with a laugh. 

Ahead of Thursday's episode, titled "Vivian's Here," ET spoke with Blake about Vivian's arrival on the scene, the contentious dynamic her character has with Annalise (and Gabriel) and theories she's a prime suspect in the (maybe) murder of Annalise.

ET: Vivian is a character who's been mentioned off and on since season five, so there was a bit of backstory for you to work with before you even came onscreen. What was your initial understanding of Vivian?

Marsha Stephanie Blake: I love the show for so many reasons, but as a black actress I love it because we see multidimensional black women from all walks of society who are professionals, but also kind of messy. I love how they're not perfect and I love that about the character of Vivian. She's a mama bear. She's trying to do all the right things and that's just real. One of the things I love about the show is there are no pure people in How to Get Away With Murder -- everyone is a little bit or a lot messy, and I appreciate that aspect of writing the characters. Also, not writing the black woman as some hero who has never done anything bad in her life or someone who is totally messed up and a drug addict -- they're all somewhere in between, and I love that. 

"Messy" is the perfect word to describe a complex character like Vivian. Do you identify with her in that way?

Yeah, but we all are, right? (Laughs.) I absolutely [identify with her]. As a mom, you make decisions you think you're doing to protect your child or to not expose your child to too much at once or to save them from heartache. When it comes back on you, you wonder "Did I do the right thing?" It's so hard to know and hindsight is 20/20. As parents, we deal with that all day long, every single day and we're always questioning -- at least me, I'm always questioning big decisions. Like, "Am I doing the right thing?" Luckily, it's never been anything as intense as what's going on with Vivian and Gabriel. I can definitely relate to her. At the end of the day, she loves her son unconditionally and is trying to protect him.

You get to go to bat opposite Viola Davis in tonight's episode. (Watch ET's exclusive sneak peek above, of Vivian confronting Annalise.) What was it like sharing the screen with her?

It's the first set I've been on where I've felt so comfortable stepping and so welcomed in such a huge way. It's so nurturing and it's a really cool set. I've worked with Viola before on a film, but that was so many years ago and I wasn't even sure she'd remember me. I played her daughter in [2006's The Architect]. But my scenes with Viola, as contentious as our scenes are, my relationship with her between scenes is great. We basically cracked a lot of jokes and made fun of each other, really. (Laughs.) We were able to jump back where we needed to go. She's so generous and welcoming and always would ask me if she was giving what I needed. And I'm like, "You've won Oscars and Emmys and Tonys, like, you're doing fine!" She's awesome. 

Vivian's son, Gabriel (Rome Flynn), has a look of despair in Thursday's episode of 'How to Get Away With Murder.' - ABC

Annalise and Vivian don't get off on the right foot and understandably so, considering the fact that Vivian's husband, Sam, left her for Annalise. How do they work through that tension, if they do?

To be honest, I don't know where the relationship goes beyond what you saw. We know who Vivian is. We know that she's Sam's ex-wife, so that can't be great that she's having these interactions with another wife [of Sam's]. We know that she knows stuff about Annalise -- she's from her past -- that other characters don't. I will say that the relationship is fraught with tension. I actually don't know where it goes, honestly. They have not told me! It's very exciting. I'm such a fan that I'm OK not knowing because I feel like I'm watching with the fans. (Laughs.) Maybe I'm a little bit ahead, but I'm not much ahead of where the fans are.

Let's talk about Vivian's other major relationship: her son, Gabriel. How would you describe their dynamic right now?

From the first two episodes, you see that Gabriel's been lying to his mom and she finds out, so that can't be good. And then, he finds out things about her that she was deceptive about. This relationship you think you have with someone, who is supposedly the person you're closest to -- he probably thought that about his mom and she thought about him -- and you find out all this deception is going on. I think Vivian feels very protective over Gabriel, as her only person out there in the world. What that means in terms of what she thinks she's doing for the right reasons but it might end up seeming to Gabriel as too much or not honest enough. It's all of that messiness when you're alone in the world and you only have one or two people out there, and you're hanging onto a relationship. He's not a kid anymore, he's a grown man. Typical mother and son stuff, really, but it's How to Get Away With Murder so you have people getting killed and murders that have happened. Now it's complicated by all this other very, very intense things with huge consequences. It's not the best, most truthful or clean relationship, I would say.

How do you rectify their relationship, which is built on a degree of deception?

You know, I don't know! If Vivian figures it out, I don't know how it'll be because I don't know how you come back after what one considers to be a betrayal or dishonesty. How do you regain the truth of your relationship? Or do you just need to start over at a different place maybe? I think that's going to be the question for Gabriel and Vivian. How do they repair this and move on? Or do we even? I don't think it's an easy thing to solve.

In the flash-forward, it appears everyone is mourning Annalise at her funeral. One of the popular theories of who may be responsible, if she is truly dead, is that Vivian is her killer. What are your thoughts?

They think it's me! I know! I was like, "Really?!" Let me tell you something, I didn't even know that Annalise gets murdered or killed or that she's dead. This is how little I know! (Laughs.) Listen, I love that people have those questions and I think that's what makes this show exciting. Like I said, I am learning things alongside everyone else and I have no idea who killed Annalise. I would say I hope it's not Vivian because I'm such a fan. That would be horrible! (Laughs.) Marsha Stephanie Blake, the actress, hopes that it's not Vivian. Vivian does not know. It's great that there is this huge mystery and this is why we love the show, that we find out things as we flash-forward that are shocking as we are dying to know more of. But yeah, girl, I have no idea!

You were also introduced in the season four premiere of This Is Us as Malik's (Asante Blackk) mother. Should we expect to see you return down the line?

No idea. Believe it or not, that show is even more secretive than How to Get Away With Murder. I didn't know how I fit into the story. The audience will out things before I do about that show. They hold it really, really close to their chest. With a show called This Is Us and another show called How to Get Away With Murder, you would think the Murder fans would be more intense, I feel like they're kind of equal. They are both wonderfully invested in the show, so yeah, they give us very little information.

How to Get Away With Murder airs Thursdays at 10 p.m. ET/PT on ABC.

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