Supergirl star talks working with that surprise guest-star

Warning: The following contains spoilers from Sunday night’s Supergirl. Read at your own risk!

A very surprising guest-star threatened Kelly’s (Azie Tesfai) life in tonight’s Supergirl.

Lord of the Rings actor Sean Astin guest-starred in Sunday’s episode as J’onn’s evil shape-shifting brother Malefic, who assumed the form of Pete, one of Kelly’s friends from the army. Hoping Kelly’s work at Obsidian could help him recover his inception powers, Malefic-as-Pete asked Kelly to help with his PTSD, which in turn gave Tesfai an opportunity to spend an entire day working with the Goonies actor.

“I was so lucky that I was the one that got to do the scenes with him,” says Tesfai. “He is such a fan of this show and it’s his daughter’s favorite show, which is why he did it. He’s seen every episode. So he cares so much and was so kind and excited and lovely. It was the best day of work I’ve had on this show by far. We got to do stunts and all of these crazy, cool things. He is such a kind person, so to see him play this character that ends up being so dark is so interesting because he’s so likable as the character Pete and as himself.”

While Tesfai had a lovely time with Astin, the same can’t be said of Kelly, who successfully (and unknowingly) brought Malefic’s twisted powers back. In the process, though, Kelly also gained the ability to see Malefic even when he’s shape-shifting, thanks to the mental connection they made during his treatment. Unfortunately, that means Malefic will continue targeting her because she poses such a threat to him. So at the end of the episode, James (Mehcad Brooks) took Kelly off into hiding to protect her while the rest of the super friends stayed behind to deal with J’onn’s brother problem. Don’t worry, though, that doesn’t mean Kelly is off the board.

“Where her and James goes is important,” says Tesfai. “You find out a lot about the Olsens and their past and a deeper level of both characters. It’s really interesting to see Jimmy with Kelly, and they have such a deep trust for one another and a vulnerability with one another. So you do get to learn more about both of them and, there is a social story that we tell there that is very important and personal to me and I’m really excited for people to watch as well.”

As EW revealed in July, Mehcad Brooks is leaving the show this fall; however, he won’t depart National City without first revealing a new layer to his character. “You’re seeing a whole other side of this character that’s been on the show for so long with his sister,” says Tesfai of their storyline in next week’s episode. “Jimmy is kind of barrels his way through things or brushes things off. Kelly is the ultimate accountability coach for that and calls him on all that stuff. So you do see this side of him that I think the audience has never seen.”

Even though Kelly and are physically separated, you can expect this latest danger to strengthen their bond. “They become a very big source of support for one another,” says Tesfai. “Things do get really, really crazy this year. So you see a new level of their relationship, and a new depth in their relationship because of all of this stuff.”

Supergirl airs Sundays at 9 p.m. on The CW.

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