Arrow's Kat McNamara Spills on That OMG Blackstar Reveal

[Warning: The following contains spoilers for the latest episode of Arrow.]

We've already done the disclaimer thing above, but seriously, if you haven't watched Arrow's latest episode, Monday's "Star City Killer," you're about to read one of the biggest spoilers of your life, so this is your last chance to turn away. All good?

OK.

OMFG, Blackstar is actually Mia Smoak (Katherine McNamara), the secret daughter of Oliver Queen (Stephen Amell) and Felicity Smoak (Emily Bett Rickards)! Fans may have guessed this was the case, but finally having it confirmed is still just so awesome. After getting into a bit of a scuffle with William (Ben Lewis) and his crew, Mia was finally forced to reveal that she wasn't Felicity's killer, she was actually her daughter.

Although we may have gotten an answer about who she is, we now have a new handful of questions about Mia's life, her relationship with her parents (why do you go by Smoak, Mia?) and whether or not Felicity could actually be alive in the flash-forwards after all. TV Guide caught up with McNamara to discuss all of this and more. Keep reading to see what she had to say!

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You obviously have experience with passionate fandoms thanks to Shadowhunters, but were you still a little intimidated taking on the role of the child of a couple that is so beloved by the Arrow fandom? Olicity Baby has its own hashtag at this point.
Katherine McNamara: 100 percent! I remember when I first found out. Beth [Schwartz], called me a few weeks after I was cast because of course they weren't revealing this in the sides. Everything -- they were dummy sides. It was a completely different character description for a rookie cop of all things. So I'm gearing up to play this really straight-laced character who really kicks butt and all this, and suddenly Beth calls me and goes, "Oh, by the way, congrats on joining the show, um, everything you know is a lie. You're actually Oliver and Felicity's daughter and there you go. Congrats!" I'm going, "Wait, I'm sorry -- pause, rewind, replay. What am I doing?"

The Shadowhuntersfandom and the Arrow fandom have always been very closely connected, so I've seen the massive support for Olicity from day one, and now having watched the show, I completely get it. I'm completely on board as well, but now having to fill those shoes, those are two very large pairs of shoes to fill. On top of that they say, "Yeah, we want her to physically resemble and have the characteristics of Stephen and have the intellect and tact of Emily's character." And I'm sitting there going, "Wait, how soon do I have to do the salmon ladder? When do I have to look like Stephen Amell? Because I need some time for this." But it's been really lovely and both Stephen and Emily have been really amazing. It's been such a collaborative, wonderful process and I'm truly honored to be taking on this responsibility.

Are you excited to see how Olicity fans react to your big unveiling?
McNamara: I am equal parts excited and a little trepidatious just because I know how strong the opinions of the fandom are. A lot of people have figured it out already, so I'm not too nervous, but you never know. I respect the fandom, and I really want them to be happy with this choice and with the way I've been bringing this character to life. I think they will be because the show's done a great job of putting it all together. I'm excited to see what happens.

How much did you try to incorporate Felicity and Oliver's traits into this character? Because you're trying to create some truth in her identity, but you're also trying to keep her identity under wraps.
McNamara: Exactly! Well, as much as possible. A lot of that's been helped by the dialogue and the situations that Mia has been put in. I did a lot of research. I did as much as I could. You know, the wiki's online about the comic characters and I had a few months to watch the entire series, so I've watched all six -- and now six and a half seasons -- of the show just to try and pick up on any mannerisms or characteristics or ways of walking into a room or ways they handle certain situations just so I can find those little nuggets that will really make it real for the fans and for all of us.

How much will we learn about Mia's upbringing and what her relationships with Oliver and Felicity are like?
McNamara:I can't say much about that, but what I can say is that the next few episodes -- and I still don't know everything because we're still shooting Season 7 right now -- but from what I know, the next few episodes reveal quite a bit about Mia and how she was raised and why she is the way she is and why she's so gosh darn angry all the time. A lot of that has to do with her upbringing and how she was raised, being this kid. A lot of it has to do with the relationship with her parents and that plays very heavily into who she became.

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Would you say Mia takes after Oliver or Felicity more?
McNamara: It depends on the situation and from which perspective you look. Physically, she very much takes after Oliver. She's extremely aggressive in that she takes on situations from the point of offense before defense, and she will take you down before you can take her down, in a heartbeat. Emotions aren't necessarily her forte. She much more prefers to deal with things on an intellectual or physical level rather than an emotional level because she has trouble dealing with emotions, which we will discover very quickly. But that's where she lies on the Oliver spectrum. But she has quite a bit of tact. She's very quippy, very witty, very clever in the sense that Felicity is. It's very indicative of her childhood, which we do get to see in a few episodes, which will be a lot of fun.

Now that William knows they're brother and sister, can we expect their dynamic to shift moving forward?
McNamara: It changes everything for both of them and whether that's for better or for worse we will find out soon.

When can we expect to start piecing together this mystery of why no one seems to recognize her for who she is? And does that play into this bigger mystery of how Star City ended up this way?McNamara: We start to get little pieces in this episode. Mia doesn't even have all of the pieces herself, but as things start to unravel and as information gets shared, more and more gets revealed as they get closer and closer to figuring out what this message that came to the Hōzen means. Now that they have more people that have more information, it starts to all build. What it really does is, it shows you how dire the world has become and really the ruin that has come to Star City to force to Felicity and Oliver to go to these lengths to protect their children.

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Mia has said she thinks vigilantes were the death of Star City and they got what they deserved. Considering we now know her parents were two of our favorite vigilantes, how did she wind up being so anti-vigilante?
McNamara: She has a very specific perception of vigilantes based on her experience as well as based on the information she had as a kid [and] what's she's learned since being on her own. All of that has come together -- plus her own personal struggles and pain and hurt that she's experienced -- it all comes together to form this very strong feeling of animosity towards vigilantes and this almost vengeful resentment of them.

Do you think Felicity could truly still be alive, or is this just wishful thinking or denial on Mia's part to admit that her mom is dead?
McNamara: I mean, at this point, she has really no information. I think at this point in the story she is operating on a blind hope that her mother is not dead. Given that their relationship doesn't seem to have resolved on the best of terms, she would probably like to resolve that.

We know Episode 16 is a completely flash-forward episode, so what can you tease about how we'll learn from spending so much time in the future?
McNamara: I just finished shooting that last week and that is really, really wonderful. I cannot wait for people to see it because that is probably the episode in which you get the most answers and you get to see quite a bit of Mia's childhood as well as some really key moments that shaped who she became and how she got to be a fighter and how she got to be this really hardened person that she is.

Arrow airs Mondays at 8/7c on The CW.

(Disclosure: TV Guide is owned by CBS, one of The CW's parent companies.)

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