‘Supergirl’: Katie McGrath on Waiting For That Luthor Gene to Kick In

Lena Luthor is a brilliant scientist, a savvy CEO, and an unwavering good friend to Kara Danvers. In fact, she’s only got one thing going against her: her name. As the sister of one of the greatest villains in comic book history, Lena’s good intentions are constantly second-guessed, and it will only get worse since she helps develop the technology that threatens the Earth heading into tonight’s Season 2 finale of Supergirl. We talked with Lena from her home in the U.K. about the Luthor stigma, being caught between two of the most evil women in television, and why she’s as curious about Lena’s future as you are.

However bad you think you have it with your mother, it’s almost certain that Lena Luthor has it worse. Lilian has tried on multiple occasions to kill her best friend and once or twice to commit genocide on all alien life on the planet. As we head into the finale, Lena has been rescued by her mother, only to find that Lilian has abandoned Kara. For a while, it seemed to Lena like she had found a more reliable female mentor — but Rhea is actually a cruel intergalactic royal intent on subjugating the entire human race.

Lena isn’t a fan of either woman right now. “I think the pain is fresher with Rhea,” McGrath says. “The relationship with Lilian, in a way, comes as no surprise. When Lilian betrays her or misbehaves, she expects it because that’s the way it’s always gone.” Rhea blindsided Lena, though, and made her feel foolish for being duped, so her anger is mostly directed at her — for now.

Off screen, however, Lilian and Rhea — played by genre vets Brenda Strong and Teri Hatcher, reunited after years together on Desperate Housewives — are as delightful as you could hope for. Hatcher is “a complete hoot, and she’s got the most zany, crazy sense of humor,” McGrath says, and Strong is “the most elegant, well-spoken comic.” Working on Supergirl is grueling — “16, 17-hour days, it’s tiring and you’re away from your family” — and McGrath loves that both women are not only brilliant actors, but also keep up the spirits of those around them. “Whenever [Hatcher] gets to set, she does a little dance for me and it always makes me happy,” she says with a laugh. “I am so grateful that they both turned out to be really good people. It’d be difficult if they weren’t.”

Part of her character’s allure, muses McGrath, is in the unpredictability of Lena’s story. “I had no f**king clue what was going to happen! I didn’t sign up for that many episodes, so I thought I was just coming in and I’d have a little small arc and that would be it,” she says. But as she made more and more appearances, the character continually bucked her expectations: “I kept waiting for the script to come in that would be, ‘Oh, I get it. There you go. She’s Lex now.’ And it never happened.”

No matter how many opportunities Lena passes up to turn on Kara, we will always be wary of that happening, but McGrath isn’t so sure that that betrayal is inevitable. “You say that she has to. Do you believe that because that’s her last name? Is this a problem that Lena’s always going to come up against? That people have pre-judged her because she’s a Luthor?” she asks. We’ve seen her brother many times and know that, like in Smallville, no matter how friendly he and Clark Kent get, Lex always was going to become evil. For Lena though, McGrath says we just don’t know. “That’s what’s compelling and exciting — to have no idea,” she says. “She is an unknown quantity. You don’t know this character because we haven’t seen her yet.” Not even she knows what Lena is capable of. “That’s what’s making me feel completely engaged with the character,” she says.

McGrath is unwilling to give up any secrets about the season finale beyond saying that it picks up immediately where last week left off — and that the spectacle rivals that of a feature film. “This is what’s great about these shows — Legends of Tomorrow and Arrow and Flash — is that they give you these mini-films with so many stunts and special effects. It’s like something you haven’t seen before on TV, and it’s entirely engaging and exciting. I think that’s why it does so well. Plus, it has me.”

The Season 2 finale of Supergirl airs May 22 at 8 p.m. on The CW.

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