'Supergirl': Katie McGrath Previews Lena Luthor's Expanded Role

Damian Holbrook
Diyah Pera/The CW

Pictured (L-R): Melissa Benoist as Kara/Supergirl and Katie McGrath as Lena Luthor

As far as messed-up TV dynasties go, we'd say the Luthor family runs villainous circles around the Carringtons, the Ewings and even the Kardashians. But on Supergirl, Katie McGrath's Lena Luthor has been bringing a jazzy new shine to a family name tarnished by maniac brother Lex and evil mother Lillian as a baller business mogul with a good heart and even better taste in pals.

So now that Lena has bought CatCo, what does that mean for her BFF-ship with Kara (Melissa Benoist)? Here, newly minted series regular McGrath shares some insider info on Lena's widening reach within the show, why she should never know Kara's secret and what was up with that James-Lena moment in last week's opener.

Congratulations on becoming a series regular. Like a lot of fans, when Lena started, I didn't know if we could trust this one. She was obviously of a bloodline that was questionable, but we're totally Team Lena right now.
Katie McGrath: [Laughs] I love you! I'm totally Team Lena right now, too. And you know what's funny? When I first signed on, I only read one script and had the same pre-conceived notions that everybody else did. You see the name Lena Luthor and think, "Okay, she's the bad guy." Then [executive producer] Andrew Kreisberg sat me down and was like, "No, no, no, no. This is the way it's going to be."

And for me that was what was the most interesting part of her, that she's this person dealing constantly with not only the pre-conceived notions of her as a woman in power, but also her as a Luthor. So she's constantly trying to exceed everybody's expectations and live up to this level that she has created to be better than her family.

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It's so cool that she's more than her family brand. She is also incredibly competent and a strong businesswoman.
Yeah. And I think we forget that about her, that she's essentially running Facebook plus General Motors plus Viacom plus Coca-Cola. She's managing all of this, and what I love about her is that she's still capable of being maybe not vulnerable, but honest. One of my favorite bits about her in the whole of the first season was when she used to go to Kara and she'd be like, "I really need a friend. I don't have anyone here."

And so that carries over into her buying CatCo. She doesn't pretend that she knows how to do it. "I've never run a media company before. I know how to make a successful business but I'm going to need you, James, to help me because you know what you're doing. I'm going to need you, Kara, to help me because you know what you're doing." And the best bosses in the world are the people who hire other people to do the things they know they can't.

Melissa Benoist as Kara/Supergirl and Katie McGrath as Lena Luthor

I think that's why so many of us really fell for her, that she was willing to open up and say she valued Kara (Melissa Benoist) as a friend.
Yeah. And also, she's never afraid to say "I'm afraid." She sees no flaw in being vulnerable and no flaw in not being perfect. She's not her brother, who's this evil mad scientist...

He's insane.
[Laughs] Let's go with crazy megalomaniac.

Well, he is locked away forever.
"Forever" is a very definite word, Damian. I'm not sure we can guarantee that. Although I don't want another Luthor on the show. I feel like I'm covering all bases!

Not to mention that the mother was bad enough!
Can you imagine? She's probably worse than Lex was. She created them. Lex is version 2.0. She's original. She's got all the bugs still in her. [Laughs] If I didn't love Brenda Strong so much, I would be worried.

There was a very brief exchange in the first episode of the season between you and James (Mechad Brooks) that had a little bit of a spark to it at the boardroom table.
I mean, listen...he's a very handsome man. Those sparks might just have been Katie and not Lena, we don't know. You can't help yourself. He's delicious. It's an extremely beautiful cast, right?

For a city that keeps getting blown up, torn apart and attacked, everyone is really good-looking.
You kinda wonder what do they put in the water in that city? [Laughs]

McGrath and Benoist's besties kick it over dinner.

So what can you tell us about what is coming up for Lena? Where is this new company and this new role that she has gonna take her?
Well, one of the great things about this season, and what I'm excited about is, now that she's part of CatCo, that has opened up a whole range of relationships for her and that whole new set of interactions. Kara is her best friend and she doesn't just have a personal relationship with her anymore. She has professional one, too. So that's another layer.

And then she also comes into contact with James and all of these people there. Lena last season was slightly isolated. Not isolated from the story—she was very involved—but from so much of the cast and so many other things going on. Like the DEO! What happens there?? I mean, c'mon! [Laughs]

Yeah, you haven't even seen what they've got going on down there.
I walk through those sets and I am so jealous. This is the coolest set here and I am never filming on it. But I would look fabulous in there.

So do you think that we might see her actually getting in on the action?
The difficulty with Lena is, Supergirl is one person and Kara is one person. You can't mess with that. That's really important. I like being the only person who doesn't know Kara's secret because I'm the person Kara can be just Kara with. She doesn't have to be the heroine. It's like Lena is her humanity and Season 3 is all about Kara struggling with her humanity. If I knew she was Supergirl, she'd have to be Supergirl all the time.

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I like it. Makes you special.
Special, yeah! So I don't know about being in the DEO because it would be like, "Hey, Supergirl. You look nothing like my best friend."

Right. "I would notice the resemblance if you wore glasses!"
It's the suit, I tell you! All the blue. That suit is very distracting. When you see Supergirl, all you see is the really cool suit. That's what happens when Superman's on set. I check it out, all of that suit.

Oh, well that view...
Tyler Hoechlin is also a very, very handsome man, isn't he? Actually, I think he's the closest Superman to the original 1950s All-American  good-boy comic-book version. You know what I mean? They've gone a lot of other ways with Superman but he's taking it back to All-American values. And I think with so much reinvention of all these characters right now, the next reinvention we've got is going back to the original. And he's so good.

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Back to costumes, Lena has probably one of the best wardrobes on television. I feel like the CW is spending a big part of their budget on her outfits. Have you borrowed any of her looks?
I swear to God, I am the least-Lena person ever. In real life, I wear sweatpants and do I have to actually wear a bra? I haven't washed my hair in five days. I was walking the dog today wearing a blanket.

That is some swag.
[Laughs] I am so not my character.

So you have no use for her outfits?
I have absolutely use when I'm playing her because I feel like it's part of her. It's like armor for her. You know? If I, Katie, ran a Fortune 500 company, I'd be wearing track suits into work because "Fuck you, I'm the boss!" [Laughs] But Lena has to project an image of power and of control—it's one of those things about being a woman. In order to be taken more seriously, you've got to come out looking strong and I think she's very aware of that.

So it's sort of her superhero outfit.
A hundred percent. Not all superheroes wear capes, right?

Supergirl, Mondays, 8/7c, The CW