Late in its fourth season, Supergirl welcomed a new cast member: Azie Tesfai, who plays Kelly Olsen, sister to James Olsen (Mehcad Brooks) and girlfriend of Alex Danvers (Chyler Leigh). Since her initial introduction, Kelly has become an increasingly important member of the Supergirl team, and Tesfai said she felt equally welcome as a new cast member -- even though she wasn't a longtime fan of the series.

During a recent, Tesfai talked with CBR about her experiences on the show, what she knew about her character, and why she stayed away from The CW's Arrowverse while she was on Jane the Virgin.

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CBR: What was it like to join the cast in Season 4?

Azie Tesfai: It was awesome. You're coming into a group of people that have this down pat. [They] were very welcoming to me and very supportive, and kind of prepared me for everything that I was coming into. So it was pretty great. It was a totally different experience than shows I've had in the past where I've kind of learned as I've gone because I've come in in the beginning. I had like a cheat sheet from everybody. So it was great.

I shot my first day and I woke up the next morning and... [Lena Luthor actor] Katie McGrath was in the lobby of my hotel... and she... came up with snacks to fill me in on everything. I was very protected and prepared.

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Were you a fan of the show and the Arrowverse before you joined the cast?

I swore I would never admit this to anyone. I was on Jane the Virgin before and... I was sick one weekend and I binge-watched all of The Originals. And then I went to set on Monday and one of the Jane the Virgin writers pulled me aside and was like, "What is going on with [your character] Nadine? You have like a weird dark energy to her." And I was like, "I binge-watched The Originals." And she was like, "Yes! You're playing her like a vampire. You're not allowed to watch any more shows." So after that I didn't watch any of the other shows on [The CW] because I'm clearly sensitive to picking up their energies and didn't want to play Nadine as a superhero.

Then, right before I started filming Supergirl I watched a lot of it, and mainly watched Alex's storyline and made a very conscious choice to be respectful and honor that and do something different. But I mainly watched Supergirl so I could offer my best for Kelly and her storyline.

Did you know much about your character going in?

The only thing I knew is the dynamic with her and Alex. Those were my scenes that I tested with with Chyler [Leigh] and that's all I really knew. I didn't know she was going to be Jimmy's sister. I didn't know any of that. That all came as a surprise way later. Because I think I got it months before it was even announced. So I just knew the bit about Alex and had communicated with Chyler a lot... And then the other storylines were great because I got to work with Mehcad [Brooks] and [Kelly] had a different side to her, having that relationship with her brother as well as the relationship with Alex.

Airing Sundays at 9 p.m. ET/PT on The CW, Supergirl stars Melissa Benoist as Kara Danvers, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen and Chyler Leigh as Alex Danvers.

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