Arming Up - Supergirl Season 2 Episode 21

Cat isn't the only one who's back. We haven't seen Lillian Luthor in awhile, but it's not surprising she would show up after her daughter has been kidnapped by Rhea.
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Cat Mentors Supergirl - Supergirl Season 2 Episode 21

Cat is back to resume her role as mentor to Supergirl. We like to think she's offering her some much needed advice. Plus, we love her makeshift chair! Did we mention how much we missed her?
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Cat's Back! - Supergirl Season 2 Episode 21

Cat is back to offer some advice to Supergirl! We hope we get to see her interact with Kara as well. We've missed her!
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Supergirl Season 2 Episode 21 Quotes

Winn: Uh guys, I just picked up on some sort of live transmission from Air Force One.
Kara: Air Force One?
Alex: Wait, don't tell me the President is heading towards the conflict and not away.
Kara: Every time I think I can't get happier I voted for that woman...

Kara: James, I'm so glad you're okay.
James: Yeah, me too. It's a war zone out there. Daxamite troops are beaming down from everywhere, setting up checkpoints, arresting resisters. It's almost like they're instituting their own Martial Law.
Winn: Not to mention the full on Independence Day going out there with the mothership hovering over the city.