‘Supergirl’ Finale: Katie McGrath Reflects on Lena’s 5-Year Journey to Her Happy Ending

McGrath also tells TheWrap about Lena’s witchy future — and how she channeled Melissa Benoist for her hope speeches

Katie McGrath
Photo: The CW

WARNING: Many spoilers ahead for the series finale of “Supergirl”

“Supergirl” has officially come to an end, and Tuesday night’s two-hour series finale gave just about everyone a happy ending — including Lena Luthor. And for series star Katie McGrath, who brought the younger Luthor to life for five seasons, that was all she really wanted.

“What I always sort of said about Lena and what I wanted for Lena was that I wanted her to finally get to be who she really is and be okay with it,” the actress told TheWrap. “She spent so many years fighting against being a Luthor, not knowing, struggling about this and finding it difficult to accept who she is.”

In the end, Lena did indeed get her much-deserved closure with the Luthor side of her family — even Lillian Luthor, which McGrath notes was a particularly difficult scene to get through — and fully stepped into her new family. Freshly minted as Esme’s godmother, the final moments of the finale saw Lena enjoying game night with her super family, confident in her place and her magical abilities.

You can read our full conversation with Katie McGrath, reflecting on her return to (mostly) fictional witchiness and the final season of “Supergirl” as a whole below.

Note: This interview has been lightly edited for length and clarity. An excerpt of this interview was originally published earlier Tuesday morning.

Katie, I believe very much in in leading with my most important question. So, are you ready?

OK, hit me. Hit me with your best shot.

In the course of the last two seasons here, you got to punch both Supergirl and Lex Luthor. Who was the best one to punch? Who was your favorite?

(laughs) Oh, who did I enjoy punching the most? God, it depends on the day! There’s something very satisfying about punching Lex Luthor. Because also, Jon is so great because when you punch him — not Jon, when you punch Lex Luthor — he always looks so shocked and in pain, which is exactly the response you want when you hit him. You know? There’s something very validating about destroying something evil.

I mean, listen, when it happened in the moment, I may or may not have fist pumped because I was so excited for you.

Damn f—ing right! I mean, it’s horrible. It’s horrible punching Jon, because he’s a nice guy. But you know what? Lex kind of had it coming, and I think Jon would agree with me. And I know Jon would agree with me.

So this season, you got to play a witch once more. And I’m dying to know how you felt about that. Did the magic just flow back to you naturally?

I mean, it’s almost like I had experience! Almost like I knew what I was doing! Because this time, it was all in Latin, [and “Merlin” was] Old English. And I was like, ‘Guys, can we not just stick with the same language? I suck at them all, but at least marginally one I have an experience in?’

But you know what? I mean, this is what’s so weird about my job or about the job of an actor. It’s like you get to do all of these like weird, different skills that you would never get in a normal life. Like, when would I ever? When would I ever get to do that? Have like, a completely fluent Latin speaker recording things for me and tell me the best way to do it. When would I get to do that kind of stuff? And that’s when you’re like, ‘my job is pretty bloody cool.’

I’m sorry, so you’re telling me you’re not actually a witch in real life?

Oh no, I totally am. Right now I’m sitting in the kitchen and I’m not actually touching any of the things that are out. I’m just using the power of my mind to stir things. It’s basically like Cinderella.

Excellent! I’m curious though, how you felt when they came to you. They say “Katie we’re making Lena a witch this season.” What was your immediate response?

Immediate response was actually “you know what, this could be kind of cool.” Because the whole idea of magic being science that we don’t quite understand yet, I could see where they were going. In that she has such a sort of affinity to the sciences that they wanted to have a storyline that would tie in with sort of the fifth dimensional and everything like that. And then my character obviously was the obvious choice to do that, because she was so well versed in science. So it made sense to me of this idea of wonder and a sense of other-worldliness. And in doing that with magic with her specifically because I’m — like you say, you know, magic is just science we don’t understand yet.

It really was so fun seeing her kind of fight that internal battle of like, ‘I’m a scientist, I believe in logic, not magic guys.’

This is what’s so great about “Supergirl,” as a show. “Supergirl” is about everybody finding out who they really are, who their true person is and accepting it. And what I always sort of said about Lena and what I wanted for Lena was that I wanted her to finally get to be who she really is and be okay with it. She spent so many years fighting against being a Luthor, not knowing, struggling about this and finding it difficult to accept who she is.

I was like, I don’t care what happens to her the character, I just want her to be happy. I just want her to have a happy ending. And for me, Lena, having a happy ending is finally accepting who she is. And so bringing that in and making her okay with magic and science and putting that all together for her, that for me was a happy ending.

I was going to say, it’s safe to say that you’re very okay with how things turned out in the finale for Lena.

She got to be godmother! She gets to be godmother to Esme, yes, I was very happy. I was like, final acceptance into the super family. Who else gets that? When I read that bit, I was like (whispers) “I made it, yes!”

NOTE: This answer, and the following question referenced a scene included in the press screener but ultimately cut from the episode when it aired.

I was really kind of hoping though, that you would get adopted by Kelly and Alex. When that suggestion came up, that’s when I was like, “Yes. Do it immediately. Do it right now.”

I was like, “Yeah, cool! I mean, my other family sucks. So this sounds like a great idea.”

Well, speaking of that other family, obviously, we’ve got to talk about this moment that she has with Lillian in the finale.

Aw, I know. It was a difficult day of filming because I love Brenda so much. And we sort of we started on the show together. And we sort of you know, we were there together the whole time. So filming that was not easy. And I was sort of almost afraid to watch it because I was like a bowl of snot. And most of that wasn’t acting, that was just me going (in a weepy voice) “Oh, Brenda it’s been five years!” And she’s just so elegant, and so amazing. And I’m like an Irish potato. Like, a mess everywhere. So hopefully it comes across.

She had such an amazing arc from where she starts to where she finishes to what she’s also gone through. And I know Brenda has a real love for the character and was very protective over her and was very much — not identified with her but really sort of understood not her as a character but her as a woman. And so it was very important to her that Lillian got a proper goodbye. I think she did because they got finally accept each other for who they were right? And that’s a lovely thing for a parent and a child.

It really was beautiful. Another moment I loved in the finale, and really kind of in season six as a whole, is Lena really got to be the one to give a couple of hope speeches of her own How was that for you, making that transition from Lena being kind of on the outskirts to being the one that’s at times even telling Supergirl like, “Hey, this isn’t right. We can’t be doing things this way.”

I just channel Melissa [Benoist] when I’m doing it. I’m like, “I don’t know how to say these words and make them sound real” so I’m like “What would Melissa do?” Because it doesn’t matter what words you give that woman, she’s such an amazing actress. She’ll be on set and I’ll be like, “I don’t know how anyone’s gonna say this.” And out it comes from her mouth and I’m like “Oh, I believe it. I would absolutely.” It’s an unbelievable skill that she has.

And I’m like, reading them and I’m like, “I don’t know how to do that. I’ll just be Melissa. I’ll just have a Supergirl moment and I’ll just do it that way.” That was the reasoning behind how I got through them because I’m, again, very cynical. Like the Irish, they make us cynical. So I’m not sure if I am as talented as her to get through them. But I did my best.

Katie, they came through. Let me just put that to bed right now.

Oh, thank god! Thank you, Andi. Thank you.

You actually get to have this beautiful conversation with Melissa at the very end of the finale, about how far you guys have come and you support her revealing herself. Tell me about filming that whole conversation at the wedding.

It’s so weird because that was one of our last days of filming. And I don’t know how much you all know about last weeks of filming a show. A) it’s very emotional, very, very emotional. And B) there’s never enough time. So, you’re filming these things, and in the moment it’s sort of — I knew my whole character was building up to this conversation with Melissa in the episode, of this lovely quiet moment. Because so much has been going on, and there’s a lot of action. This is a very lovely skill moment between the two.

You just want to get it right, and you don’t have a huge amount of time. And at the same time, while you’re trying to get it right, there’s also in your head, you’re like, ‘Oh my god, this has been five years for me, this is kind of a goodbye.’ This is five years! And you’ve got all this going on in your head and you’re trying to get it right and you’re trying to do it justice and trying to do the words justice and it’s a lot. It’s a lot. It’s an emotional moment.

Part of all that last episode was not just Lena, it’s Katie as well. Like, these actors, this crew, they all became my family. We spent nine months of the year together, you know, making this show — we were each other’s lives. And you’re not just saying goodbye in the moment as Lena and the rest of the super friends. You’re saying goodbye as Katie and the rest of my friends. So there’s a sort of added weight towards the themes that it becomes — it was a big week. The last week was a big week.

OK so, before we go — we’re happy with Lena’s ending. But, obviously fans are going to continue this world in their own mind. So in your mind, as Katie, what does Lena’s future look like? Because she’s got the Lena Luthor Foundation. So is she now just this witchy philanthropist?

(laughs) Oh my god, that’s it now! She’s a witchy philanthropist. That’s the best. Like what do you want to be when you grow up? I want to be a witchy philanthropist. Done. Sold. That’s it. That is like, now any time anyone asks me about my future plans, I’m a witchy philanthropist.

“Supergirl” is now streaming on Netflix and the CW app.