The CW's Supergirl has cast transgender activist Nicole Maines as television's first trans superhero, in a role that appears to introduce another member of DC's Legion of Super-Heroes to the drama.

As announced this evening during Warner Bros. Television's Hall H presentation at Comic-Con International, Maines (The Trans List, Royal Pains) will play Nia Nal, a new addition to the CatCo reporting team described as "a soulful young transgender woman with a fierce drive to protect others." Her Season 4 story arc will see her fulfill her destiny as Dreamer.

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Longtime comics readers will undoubtedly recognize the similarity between the names Nia Nal and Nura Nal, the fan-favorite DC character better known as Dream Girl from the Legion of Super-Heroes. She was briefly known as, yes, Dreamer in the 1990s. Introduced in 1964 in Adventure Comics #317, Dream Girl comes from the planet Naltor, where most of the inhabitants possess precognitive abilities, in which they experience visions of the future through dreams.

Nicole Maines on Royal Pains

Maines, now 21, was the pseudonymous plaintiff in Doe v. Clency, the landmark 2013 case in which the Maine Supreme Judicial Court ruled it's unlawful for schools to deny transgender students access to the restroom consistent with their gender. She appeared in the HBO documentary The Trans List, and guest-starred as a transgender teen on the USA Network series Royal Pains.

There's no indication yet whether Maines' character on Supergirl will depicted as a member of the show's Legion, which so far has included Mon-El, Brainiac 5 and Saturn Girl among its ranks (Chameleon was also mentioned).

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Maines is joined in Season 4 by fellow newcomers April Parker Jones (Jericho, The Last Ship) as Colonel Haley and David Ajala (Doctor Who, The Dark Knight) as Manchester Black. Jesse Rath, introduced in Season 3 as Brainiac 5, and Sam Witwer, who will play Agent Liberty, were previously announced as series regulars for Season 4.

DC's Legion of Super-Heroes introduced a trans character in 1992, when it revealed that Element Lad's longtime romantic interest, the team's Science Police liaison Shvaughn Erin, had been born male but had taken a futuristic drug called Profem to change genders.

Starring Melissa Benoist as Kara Danvers, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen and Chyler Leigh as Alex Danver, Supergirl returns on a new night, Sunday, Oct. 14, at 8 p.m. ET/PT on The CW.