Chyler Leigh as Alex
Chyler Leigh revealed that Alex’s abductor in Season 2, episode 19 of “Supergirl” is someone who knew Alex and Kara (Melissa Benoist) when they were young. The CW

As previously reported, Alex (Chyler Leigh) gets kidnapped in Season 2, episode 19 of “Supergirl.” But who actually is her kidnapper?

In a recent interview with TVLine, Leigh revealed that her character’s abductor is someone who knew Alex and Kara (Melissa Benoist) when they were young.

“This episode is called ‘Alex,’ and there’s a guy who comes back from Alex and Kara’s past,” Leigh revealed to the news outlet on the Vancouver set of the CW series. “In the [Supergirl] pilot, you saw a young Kara miraculously save a girl from car. Well, this one guy saw her do it, and knowing that she had these powers, he figured out that Kara is Supergirl.”

READ: Kara and Superman fight each other in new set photos from “Supergirl” Season 2 finale

The kidnapper then uses this knowledge as part of his plan, which Leigh described as “big” and “elaborate,” to break his father out of prison. “Hello, Supergirl. Walk into prison and break my father out within the next 36 hours or your sister will die,” Alex’s abductor tells Kara over the phone in the trailer for the episode.

Kara teams up with Maggie (Floriana Lima) to save Alex. But because Kara and Maggie have always had different approaches to apprehending criminals, they find themselves at odds as they figure out the best way to save the woman they both care about.

“[Kara and Maggie] are both women who are very strong and opinionated and stubborn, and they very much have their own way of figuring out a problem,” Benoist said. “[So as the work together] they don’t necessarily agree on how to deal with the fact that the person that’s the most important to both of them is missing and in danger.”

“They’re both strong, opinionated women who really are passionate about their work, so they’re going to butt heads a bit — but not in any aggressive, bad way,” Lima added of the tension between Kara and Maggie. “[It’s] more along the lines of, ‘I want to go this way,’ and Kara, Supergirl, wants to go another route. And we’re both telling each other, like, ‘No, that’s not the safest plan.’ We both think we know Alex more than the other.”

Executive producer Andrew Kreisberg also previewed the episode during a recent chat with Entertainment Weekly. “What’s interesting is it’s really an episode about jurisdiction,” Kreisberg said. “It’s really a Maggie-Kara episode. It starts with them at loggerheads about, where does the police’s jurisdiction end and where does Supergirl’s begin? They’re on opposite sides of that. Maggie is obviously more for the police and Supergirl is more for Supergirl.”

“Who gets to make the decisions to save Alex: The sister or the girlfriend?” Kreisberg continued. “It’s great because neither of them are right and neither of them are wrong, and they both love her and both want her back. It’s just a question of who’s willing to do what to bring that about?”

“Supergirl” Season 2, episode 19, aptly titled “Alex,” airs on Monday, May 1 at 8 p.m. EDT on The CW.