Supergirl introduced the first transgender superhero on live-action television in Dreamer, the superhero persona of CatCo investigative reporter Nia Nal.

In honor of Trans Day of Visibility, star Nicole Maines posted an emotional TikTok video showing affirmation of her transgender identity, encouraging fellow transgender individuals to "shine even brighter."

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Season 5 has seen Dreamer take more of the spotlight, with a transphobic villain targeting Dreamer and her roommate to drive Nia out of the superhero game for good. With Supergirl's support, Dreamer was able to soundly defeat her most personal enemy.

Nia was introduced at the start of Season 4, as a political speechwriter that came to National City to work in journalism. As the season progressed, Nia revealed her transgender status after being appalled by the growing xenophobia across the country. After sharing her extraterrestrial heritage, Nia became the superhero Dreamer and began a romantic relationship with Brainiac-5 while continuing to work alongside Supergirl in defending the city.

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Airing Sundays at 9 p.m. ET/PT on The CW, Supergirl stars Melissa Benoist as Kara Danvers, David Harewood as Martian Manhunter and Chyler Leigh as Alex Danvers.