Supergirl type TV Show network The CW genre Superhero Where to watch Close Streaming Options

Laura Vandervoort will guest-star on an upcoming episode of Supergirl, the producers announced on set during the Television Critics Association’s press tour on Monday. (EW first broke the news last June.)

The Bitten star, who played Supergirl on Smallville, will portray DC Comics superheroine-turned-villain Indigo for a recurring role starting with episode 15. Indigo is described by producers as a living, strong-willed supercomputer who was sentenced to Fort Rozz after turning against the people of Krypton. Now on Earth, Indigo will let nothing stand in her way.

“She’s badass,” executive producer Andrew Kreisberg says. “She’s going to look awesome. Definitely not going to look just like Laura. Being one aspect of the Brainiac program, she comes in through computers, so Winn is actively involved in that episode. She has a very interesting backstory. She was one of the Fort Rozz prisoners, but how she came to be and how she ended up on the prison, and what she’s been doing on Earth is part of the fun and the surprise of the episode.”

Adds executive producer Sarah Schechter: “Her backstory fits in quite nicely and is integral to our overarching mythology.”

Vandervoort is not the first former Supergirl to appear on the CBS series starring Melissa Benoist; Helen Slater has appeared in at least two episodes as Kara and Alex’s mother, and all three Supergirls will unite in an episode later this season.

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In other Supergirl news, we’ll meet the show’s take on Master Jailer. Jeff Branson will recur as the forceful and unrelenting jail guard on Fort Rozz who showed no mercy. Now on Earth, he is hellbent on catching all of the Fort Rozz escapees and brutally bringing them to justice.

“One word: Chains,” Kreisberg says.

Also, the upcoming 13th episode is inspired by Alan Moore’s Superman story “For the Man Who Has Everything,” in which Kara finds herself back on Krypton with no knowledge of how or why she’s there; what she’s actually facing is the Black Mercy, a plant that taps into the pleasure centers of a comatose person’s brain to create a vision of the host’s perfect life.

“There was something about that particular story that, to me, was almost even more resonant for her,” Kreisberg said, noting that it’s a good guess that this will be the episode that features young Kal-El. “For Superman, when it happens to him, it’s his wish for something that he never had. But for her, she wants something back that was taken from her. It really is like her stepping into this fantasy of what life would’ve been like if she had never left Krypton and had grown up there, if her parents were still alive, if she had grown into the person and the life that she wanted to lead. Again, because it’s coming at a time where she’s feeling so low about her life on Earth, it becomes that much more potent… She’s actually getting back everything that was taken away from her and the only way out of it is to reject it. Imagine how horrible that’s going to be.”

Supergirl airs Mondays at 8 p.m. ET on CBS.