Katie McGrath Knows How Learning Supergirl's Secret Would Affect Lena

Time and time again, Supergirl's Lena Luthor has proven she’s loyal, compassionate and quite capable of carving out her own path in life. Why is it, then, that people automatically lump her into the same category as her other nefarious family members? Could she really be a ruthless, over-ambitious, evil villain willing to do anything to further her own agenda and obtain power, or is she simply what she appears to be -- a good person, and a great friend.

Lately, certain circumstances and individuals have crushed her spirit, and in the season's penultimate episode, her mother Lillian once again lied to the good guys and betrayed Supergirl. However, both Lillian and Rhea are about to learn a valuable lesson -- never, ever underestimate a Luthor.

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Ahead of tonight’s season finale, McGrath spoke with CBR about the Luthor legacy, Lena’s mommy issues, the last stand against Rhea and what if Lena learned Kara’s secret.

CBR: There is both a stigma and strength associated with Lena’s family name. What does it mean for her to be a Luthor?

Katie McGrath: Everybody has this preconceived notion because of her last name. She feels that no matter what she does, at times people are always going to put her in the same box as Lionel, Lex and now, obviously, with her mother, Lillian. That’s what she’s constantly struggling with. In the back of Lena’s mind, she feels no matter how much good she does, ultimately, everybody believes that she is going to go the same way as her brother. That’s frustrating for her.

Lena is an extremely intelligent woman. How did she ever get blindsided by Rhea?

I think she was just so desperate for somebody to tell her she was doing an excellent job. If you think of all the stuff that she went through alone this season with her mother – to have somebody who, in an unqualified way, say, “You’re amazing. You are brilliant. I’m so proud of you. I’d be happy to have you as a daughter.” – How can she not respond to that? Lena was just so desperate for that.

How responsible does Lena feel for the Daxamite invasion and the current state of National City?

I think she feels a fair whack of responsibility on that one, to be honest. For somebody who prides themselves so much on their intelligence, for who it’s such a large part of their persona - to be taken in, in such a massive and almost obvious way - she feels extremely responsible. That’s what drives her to do what she does in episode 22. It’s a direct response to what she feels with Rhea and the destruction of National City.

Lena’s mother issues unfolded during the year. Was Lillian betraying Supergirl the last straw?

It’s safe to say there are a few scenes involving Lillian and Lena, which resolve the matter one way or another. For Lena, a lot of what happens in Season 2 will come to some sort of resolution.

What are your thoughts on Lena’s friendship with Kara?

It’s a relationship of equals. As far as Lena is concerned, Kara is Kara. Kara is not Supergirl. For Lena, she has a friend on the same level as her, who is fantastic at their job, is intelligent, smart, capable and strong. What’s lovely is it’s two normal women figuring out life together as friends. I think that’s what is important to Lena, that she has somebody where she doesn’t have to be the head of the company. She doesn’t have to be somebody’s daughter. She can just be herself. And, Kara can be that. She doesn’t have to be Supergirl or a reporter. She can just be the flawed human being that we are.

Considering Superman’s history with the Luthors, how do you believe Lena would react if she discovered Kara’s secret?

A really large part of me believes Lena would be hurt that she didn’t know, but she would understand. At the same time, there’s such a drive for Lena to be so different than the rest of her family, and she is the opposite of them. I know she would respond in the opposite way, that she would understand.

Now that Lena has been rescued from the Daxamite spaceship, where does she fit into the finale and the war against Rhea’s forces?

She’s extremely important. At the end of the day, Lena is one of the smartest people within National City. She is intelligent and experienced. She has LexCorp, L-Corp, behind her. You would be wrong to think she is down and out when she is such a fantastic woman, and such a strong woman. You would be wrong to discount what she could bring to the battle.

How will the death of her ex-lover Jack affect Lena in the future?

That remains to be seen, which is pretty exciting for Season 3. That’s one of the reasons I wanted to come back and do that. There were so many little seeds that were planted throughout Season 2. That stuff with Rahul is part of that, it’s to see those little moments that are going to become massive moments. That’s what is exciting about being an actor and that’s what we want to find in every job moving forward.

You have been bumped up to series regular for Season 3. What are you hoping the writers will explore?

Every time I get a script from them, I am completely blown away and amazed that they want me to be in the show any more than I am, but I’m so grateful. They have this great core character that they’ve created, and then they keep throwing these different things out at her. I have complete faith in the team. I know nothing about Season 3, but I know it’s going to be as exciting, and as edge of your seat and nail-biting, as this one.

Airing Monday at 8 p.m. ET/PT on The CW, Supergirl stars Melissa Benoist as the Girl of Steel, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, Chyler Leigh as Alex Danvers and Jeremy Jordan as Winn Schott, with appearances by Calista Flockhart as Cat Grant and Tyler Hoechlin as Superman.

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