After finding out the leader of CADMUS is actually Lena Luthor’s (Katie McGrath) mother, Lillian (Brenda Strong), the anti-alien agenda Kara (Melissa Benoist) has been fighting against all year became much more clear.

After all, why wouldn’t Lex Luthor’s mother be harboring a grudge against aliens, when the most famous one on Earth sent her son to prison for the rest of his life?

Now Lillian has Kara’s blood, which she’ll no doubt use for evil purposes. We caught up with Brenda Strong to ask her about Lillian’s master plan, her relationship with her daughter, and whether or not she thinks there’s any hope of redemption for her character.

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How far do you think Lillian will go to pursue her anti-alien agenda?

I think that has been her single-minded focus from the very first episode that we were introduced to her, before we even knew that she was Lillian Luthor. We knew that there was some kind of vendetta and mission that she was trying to accomplish. Once we found out that she’s actually a Luthor, I think the vendetta became very clear.

It’s operating on two levels. One is a personal level against Superman (Tyler Hoechlin) for Lex and also in protection of her daughter, Lena (Katie McGrath) against Supergirl… Then there’s the more global one… She really, honestly sees aliens as a threat to humanity and has a mission to eradicate the earth of all alien influence.

I think there’s a real fear there that in a way mirrors a lot of what’s going on globally with us. We see “other,” and things that we don’t understand, as a threat. Certainly people who have more power in certain respects than we do — it gets scary. She sees it as an opportunity to not only right a wrong that was done to her son, but also to save the world. I think whenever you have that kind of large ambition there’s a lot that can go wrong, and there’s a lot of enemies that you can align with who feel the same way. There’s also a lot of people who will surprise you.

Do you think those two motives are kind of her redeemable qualities?

I think she deeply cares for her children. Most of her actions came out of protection of them. I think she’s a huge mama bear, and I don’t think any villain thinks they’re a villain. I think they are just single-mindedly focused on their goal. With that comes the Achilles heel of not always seeing things in  their entirety. She only sees what she wants to accomplish, and anything that she can do to accomplish that is what she’s going to do.

I think there’s so much juiciness in being able to play someone like this, who’s doing it for love, not just power. I don’t think she really craves power. It’s not about power for her, it’s about protection. I think that’s a whole other intention that we can all see as a mirror, both societally and globally.

I think it’s a great conversation to have through this tapestry of comic book hero and villain TV show. I think the Berlanti universe is really exploring some wonderful moral and social dilemmas in a way that allow people to think more about how this affects them personally in their real lives.

Do you appreciate these real life issues “Supergirl” is trying to incorporate?

Absolutely. And it’s so personal, even with Alex coming out, you know, the discovery of her own feelings and her wanting to come out to her mother and the threat of “Will she betray me, or won’t she? Will she not love me anymore?” There are so many really sweet, amazing, vulnerable things that are playing out in this comic book epic series… It’s great that’s it not just about “Who is Supergirl fighting this week?”

chris wood melissa benoist supergirl cw Supergirls Brenda Strong: Lillians Medusa Virus can eradicate aliens on earth

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What can you tell us about Lena and Lillian’s relationship coming up?

It’s so complex, this mother/daughter relationship. First of all, just being part of the Luthor universe, I’m sure, has its own curses involved in it — and the fact that Lena is adopted, and not quite sure of her place in the family… Lillian hasn’t always been the warmest mother, when it comes to showing her daughter affection or approval, and so there’s a lot of tug-of-war, of hurt, and feelings that have not been resolved yet between them.

The scenes between Katie McGrath and I are always laced with such energy and tension and vulnerability. It’s so much fun to play. I’m really enjoying working with her and exploring this mother/daughter relationship on screen. I know most daughters and mothers, as much as they love each other, there’s always a little bit of competition there, and there’s always a little bit of tension. So it’s really great to be able to play in the field of that relationship and see what comes up. I think Lena in many ways is [Lillian’s] vulnerability.

Do you think Lena has any of her mother’s dark streak in her?

I don’t think anybody is black and white in this show, really. I think she is a Luthor, but I think she’s really trying to set herself apart from her family’s legacy. It’s very clear that she is trying to do good in the world, and wants to befriend Supergirl and cut a different cloth for her family’s legacy. I think that’s apparent, and probably what hurts Lillian as well.

It’s like, “Well, why can’t you just be like us?” So I think she’s definitely swimming upstream. Whether or not that changes, we’ll have to see. I think her intentions are pure, insomuch as her relation to Supergirl. Yeah, I don’t think anybody’s black and white, I think everyone is grey.

Can you tell us anything about Project Medusa?

Well, you know the entire episode “The Darkest Places” was about entrapping Supergirl, so that I could drain her of her energy, get her blood, and use it as the key to unlock this secret that has been lying hidden.

The source of the Medusa Virus is interesting, and then what it can do is very threatening. It has the ability to really give Lillian the power to fulfill her plan, which is to eradicate aliens on earth. That is her mission, and this particular episode is the culmination of being able to take this Medusa Virus and fulfill my dream. So it’s a very exciting episode.

“Supergirl” airs Mondays at 8 p.m. ET/PT on the CW.

Posted by:Lindsay MacDonald

Lindsay MacDonald is a Los Angeles based entertainment reporter with an affinity for CW superheroes. She graduated from Pepperdine University with a major in Media Studies and a borderline unhealthy obsession with TV in 2012. She would much rather spend the day binge-watching ‘The Flash’ or sorting ‘Game of Thrones’ characters into Hogwarts houses than venturing outdoors. TV words to live by: “Never ignore coincidence. Unless, of course, you’re busy. In which case, always ignore coincidence.”