Supergirl: Lena Luthor And Rhea Form Mother-Daughter Like Relationship

04/30/2017 05:22 pm EDT

We've been waiting all season for Lena Luthor (Katie McGrath) to turn to the dark side, and after the loss of Jack Spheer -- her former boyfriend of two years, who she still harbored feelings for -- in the previous episode, it appears as though Lex's sister now has ice coursing through her veins.

"When Lex was arrested, my mother was there," a grieving Lena told Kara. "My mother saw her son, dragged bleeding and raving from her house. And when I got there, Lillian was tidying his room like he'd been away on a business trip. ...That's how I feel. Cold and calm. Until I think about Beth dying in jail, and then I feel warm for a minute." She added, Loss does strange things to my family and I have lost a lot of people... I think when I feel things again I... I'm gonna be very, very afraid .. of the person I might be."

Making matters worse, Queen Rhea (Teri Hatcher) -- Mon-El's diabolical mother -- showed up at Lena's office and told the emotionally-vulnerable CEO of L-Corp that she has a business proposition for her. Of course, it won't be strictly business between the two. Rhea will be the mother Lena never had.

"What's interesting about it is Rhea has got her master plan and she obviously does not come in peace," executive producer Andrew Kreisberg told EW. "But what's interesting to us as writers, and what I think Teri and Katie do so beautifully in their story line together, is Lena's lost her father, she's lost her brother, now she's lost Jack. She's desperate for a mother to come along and help her, protect her, and take care of her; obviously, Lillian is not that person. Then along comes Rhea, who is offering to be this guide, this mentor, and this supporter, and somebody who is truly proud of Lena and truly cares about her. Lena is uniquely vulnerable to what Rhea is offering."

The relationship works both ways. Lena will be the like daughter Rhea never had. "By the same token, Rhea has been rejected by her child," Kreisberg explained. "So as much as Rhea has her ulterior motives, in Lena, she's looking at the daughter she never had, because this is somebody who is smart, creative, and looks up to her. While there is the grander plot and scheming going on, you really have a daughter who needs a mother and a mother who needs a child. That's what makes their pairing together so interesting and nuanced."

Check out "Alex" preview images in our gallery below!

Alex (Chyler Leigh) is kidnapped and the kidnapper threatens to kill her unless Supergirl (Melissa Benoist) releases a notorious criminal from prison. Supergirl and Maggie (Floriana Lima) have always had different approaches to apprehending criminals but this time they must work together to save Alex. Meanwhile, Rhea (guest star Teri Hatcher) has an interesting proposal for Lena (Katie McGrath).

Rob Greenlea directed the episode written by Eric Carrasco & Greg Baldwin.

MORE: Supergirl: Martian Manhunter And Livewire Concept Art / "Alex" Photos Released; New Details On Her Kidnapper / How Supergirl Influenced Wonder Woman's Marketing / Supergirl: General Zod Makes An Appearance In New Set Photos, Video

Distributed worldwide by Warner Bros. International Television Distribution, SUPERGIRL is executive produced by Greg Berlanti (Arrow, The Flash), Ali Adler (The New Normal), Andrew Kreisberg (The Flash, Arrow) and Sarah Schechter (Blindspot, The Mysteries of Laura). Supergirl is based on the characters created by Jerry Siegel and Joe Shuster and appearing in DC Comics, by special arrangement with the Jerry Siegel Family.

"Alex" episode of Supergirl airs Monday, May 1 at 8 p.m. ET/PT.

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