'Supergirl' Cast and Crew Tease Brainy and Lena's Bond

As The CW's Supergirl progresses into its fourth season, a budding friendship is apparent between the no-nonsense Lena Luthor (Katie McGrath) and the comedic relief Brainiac-5 (Jesse Rath).

According to Supergirl executive producer Robert Rovner, the two identify with each other so much because they're both genuinely brilliant.

"Brainy has found an unlikely confidant in Lena Luthor, and that's because both characters are "the smartest people on the planet," Rovner told TVLine.

Rath agreed, before adding the fact that both of the characters are the "black sheeps" of their respective families, mainly in part because they didn't follow along in the "family business" of being villainous.

"They also have these relations to these horribly evil people, and they are kind of the black sheep of the family — 'cause they're good," Rath added.

As this season progresses, Lena's going to need all of the support she can get as the show is setting up to introduce her estranged half-brother Lex to the Arrowverse.

"It's a big Lena story this season," Rovner explained. "[Lex] weaves into the narrative we're telling. We're excited about the possibilities of who might step into the iconic role."

"We're beyond excited to introduce iconic villain, Lex Luthor, to Supergirl and to weave him into our story this season," Robert Rovner and Jessica Queller said in a statement when the announcement was made. "We've talked about having Lex on the show since it's inception and we're excited to have him finally arrive. We can't wait for him to shake things up in National City and watch him go toe to toe with not only Supergirl, but his sister Lena Luthor."

The synopsis for tonight's episode can be read below while the stills and promotional images can be found here.

THE POWER OF THE PEN

Colonel Haley (April Parker Jones) makes a surprising decision regarding Supergirl (Melissa Benoist). Kara writes s series of articles highlighting aliens in National City in the hopes that humans will stop being so fearful of them. Unfortunately, the article puts some of the aliens in harm's way.

David McWhirter directed the episode written by Maria Maggenti & Aadrita Mukerji.

Supergirl airs Sundays at 8 p.m. ET on The CW. "Parasite Lost" airs tonight, November 11th.