'Supergirl's Azie Tesfai on Kelly's Struggle, Alex & That Special Guest Star

Meredith Jacobs
Q&A Dean Buscher/The CW

[Warning: The below contains MAJOR spoilers for Season 5, Episode 3 of Supergirl, "Blurred Lines."]

Kelly runs into quite a bit of trouble in Sunday's episode of Supergirl, all because she wants to help an old friend — or at least someone she thinks is an old friend.

In fact, she ends up with a target on her back, and for her safety, she has to leave, with James (Mehcad Brooks) by her side. "She's not going to be gone for very long," Azie Tesfai tells TV Insider. "There's things happening. She'll get back to it."

Here, Tesfai discusses "Blurred Lines," Alex (Chyler Leigh) and Kelly's relationship, working with guest star Sean Astin, the crossover, and more.

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How does she feel about having to leave for her safety — and so Alex isn't distracted?

Azie Tesfai: She's torn. She deeply cares about these characters and there is scary stuff happening. To run away and leave, I don't think is in her personality. I don't think it's in the Olsen personality. It feels very unnatural, but she also doesn't want to be the reason anyone gets hurt as well, and that's why she agrees to begrudgingly [leave].

How will Kelly's experiences with a shapeshifter change her? She's so open, but as we see, Alex is right to worry about that. And Kelly acknowledges that before she leaves, that she was too trusting.

It's something that we all struggle with, which is, you want to expect the best in everything and everyone. This world is such an extreme case of our reality, obviously, but Kelly's core of who she is is that she will always help and she will always be kind and she will always see the good in everyone.

(Colin Bentley/The CW)

She has been thrown in the deep end of this world. She never really knew this side of her brother's life and she's come into town and a lot has gone down and a lot more will go down and she's trying to navigate it while understanding it at the same time ... and also survive and care for the people around her. You will see her try to grasp this world, grasp her place in it and where she fits in with the people around her and the people she cares about. It is a struggle.

Kelly and Alex's relationship is going really well. What are you enjoying most about that relationship?

Working with Chyler. I did the chemistry read with Chyler and that is the most I've wanted a role was after we finished that read. ... This season in particular, specifically even in the last three episodes — we're on Episode 10 now — I've had moments with her where we've forgotten there's other people in the world and to get to work as an actor with someone you go on the ride with and really trust is so rare and so special.

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What's coming up for them? In a couple episodes, they're celebrating an anniversary.

They have a dateaversary. They're pretty adorable. They're just so sweet and pure and kind and healthy and adult. They have some milestones coming up. Nothing in this world is peaceful for more than two minutes, so they navigate their separate problems and survivals with each other and that allows them to know each other in a deeper level. They really care about one another. There's nothing like past experiences to get you to know who someone is and different layers of yourself. They will explore that together this season.

Moving on to Kelly's relationship with her brother, how does she feel about James' job opportunities this season? And how is she going to handle his upcoming departure?

Kelly has always believed James has more potential than he has. She sees her brother in the best light and thinks he can truly change the world. Him leaving his job with this new character coming in wasn't a bad thing in Kelly's eyes. She thought, "Now you can go on and grow and help people in other ways."

(Dean Buscher/The CW)

The departure is hard. I can't say how or when, but it was hard for Kelly. It's hard for me as an actress because I love Mehcad. It was hard for the whole cast. He is very close to every single person on this show. It was very personal for everyone. When that episode airs, you'll see there's a lot of sadness from every single character and every single actor with that departure. You really feel it. It was heartbreaking to do.

What will we see coming up for Kelly at work in her continued work with new technology and with Andrea and Obsidian North?

There's all these interesting studies and research done about PTSD and different kinds of medicine and that's essentially where Kelly's interest lies. Her passion is mental health and helping people heal in a real way and dealing with PTSD and trauma, which you can't in life access by traditional therapies. You need other means.

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She's using these tools to really help people, and as you see in the first half of the season, there is success in that. I've always been a fan of Obsidian, contrary to everyone else. I understand why Kelly is so passionate about it and believes in the potential of it.

Speaking of that, she thinks she's helping an old friend in this episode, but it's J'onn's brother pretending to be someone she knew. How would you describe Kelly's relationship with the real Pete and will we meet him?

I can't say anything about the future with that character, but Sean [Astin] is like magic in a bottle and is the most amazing actor and human. He came in and we shot all of that stuff in one day. I think we did 11 scenes in a day. We had a full day together. He has seen every episode of Supergirl because it's his daughter's favorite show and he watches it with her. He brings such a lightness to set and I felt so lucky I was the one who got to work with him because I had the best time.

(Dean Buscher/The CW)

I hope [he returns]. Sean and I discussed what we thought, and I think Kelly and Pete had a lot of history together, clearly because she was willing to risk her job to help him.

And of course I have to ask about the crossover. Anything you can tease about what's leading up to it and perhaps any involvement from Kelly?

I can't say anything about who's in it or whether Kelly's in it. It changes everything. This is a heavyweight crossover, where everything shifts in every capacity. It's pre-crossover and post-crossover in this world. It is so good and so cool and there's so many cool people that are going to be on it that no one knows and won't know until it airs. It will blow your mind. It's so exciting.

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Supergirl, Sundays, 9/8c, The CW