Supergirl: Meaghan Rath to Play a Female Brainiac 5

Supergirl's San Diego Comic-Con panel and Saturday had quite a few interesting reveals about The CW series' upcoming fifth season from the first trailer for the upcoming season to surprise announcements about Lex Luthor's return for "Crisis on Infinite Earths. The CW also revealed casting information about new characters coming to National City this fall including Meaghan Rath who will be joining Supergirl as a new Brainiac-5.

Jesse Rath, who currently plays Brainiac-5 aka. Brainy on Supergirl, happens to be the actress' real-life brother and told the audience that it was something he had been pushing for since he was cast in his role.

"[This is] something that I've been pitching since I got the role," Jesse said. "You can't talk about Brainy without talking about his family. My real-life sister will be joining the show, Meaghan Rath. She will be playing a female Brainiac-5."

Other than the announcement at the panel, little else is currently known about this new female Brainiac-5 nor do we know just yet how many episodes she is expected to appear in. As for Rath herself, she is best known for her lead role as Sally Malik on Being Human where she co-starred alongside Supergirl alum Sam Witwer.

In addition to Rath's casting, Supergirl also revealed that two new characters will be joining the action for the upcoming season DC's Andrea Rojas (aka Acrata) and renowned reporter William Dey.

Julie Gonzalo (Veronica Mars, Dallas, Eli Stone) will star as DC character Andrea Rojas (aka Acrata). A polished businesswoman and heir to a Central American tech empire, Andrea Rojas (aka Acrata) is now making a hostile advance into the world of media. Unapologetic and unafraid to make waves, she also holds a mystical secret. Gonzalo will first appear as Rojas in the season premiere.

UK-based actor Staz Nair — who played Qhono, a Dothraki warrior loyal to Daenerys Targaryen on Game of Thrones — will play hardened reporter William Dey, an original character created for the series. On the surface, he's a cynic and a sellout who looks down on Kara's earnest idealism. Dey's not interested in making friends, he just wants to get the story — but his ties to the criminal underworld could prove problematic. Nair as William Dey will also make his debut during the season premiere episode.

The moves toward changing the media landscape in Supergirl's National City may play into the recent report that Mehcad Brooks, who plays CatCo chief James Olsen, will be leaving this season.

Supergirl returns with its fifth season in October on The CW. Facing a new threat and featuring a new costume, Kara Danvers (Melissa Benoist) and her team of allies will square off with Leviathan — bringing Supergirl closer to synching up with the comics than almost any show in comics history, since Brian Michael Bendis is writing a Leviathan-centric event that finds a lot of its story core in what he has been doing with the Superman titles right now.

Supergirl premieres on October 6, 2019, on The CW. Keep your eyes on ComicBook.com all weekend long for more on Supergirl, "Crisis on Infinite Earths," and more from San Diego Comic-Con.