'Supergirl' 's Katie McGrath Opens Up About Emotional Series Finale: 'You Want to Get It Right'

Supergirl's two-hour series finale proved to be an emotional ride indeed.

The Melissa Benoist-led series concluded its journey Tuesday on The CW after six seasons. And according to Benoist's costar Katie McGrath, it was important for those involved in the production to do right by the viewers in the end.

"You just want to get it right, and you don't have a huge amount of time," McGrath, 38, told The Wrap. "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."

McGrath, who played Lena Luthor, said realizing she'd no longer be working with her Supergirl colleagues made filming the end all the more challenging.

"Part of all that last episode was not just Lena, it's Katie as well," she said. "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."

"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," she continued. "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."

Supergirl premiered on The CW in 2015. The series followed Superman's cousin Kara (Benoist) navigating her own superhero career.

Ahead of the final episode, Benoist, 33, bid farewell to the show and thanked fans for their support.

"Thank you to every incredible person who ever played a part, however big or small, in making this show tick. We accomplished so much and I'm so proud of all of us," she wrote on Instagram.

"Thanks most of all to each and every one of you who saw us through and watched to the very end," she added. "Hope you love how our story ends."

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Benoist previously teased the possibility of slipping back into her cape down the line, saying "there probably will be opportunities" to do so.

"It would have to feel right for the character, and I know they would probably do it justice," the Glee alum told Digital Spy in July. "I love playing with Grant Gustin [The Flash]. I love Tyler Hoechlin [Superman] and Bitsie Tulloch [Lois Lane] on Superman & Lois. So no, I'm not opposed to it."