First transgender superhero announced for The CW's 'Supergirl' Season 4

Nicole Maines gained national attention for her battle against her Orono, Maine school district over her right to use the girls' bathroom. (AP)

The CW's "Supergirl" series will make TV history in Season 4 with the introduction of the first transgender superhero.

Nicole Maines, a transgender activist and actress who previously won a discrimination lawsuit after her school refused to let her use the girls' bathroom, will appear on the show as the DC comics character Nia Nal, aka Dreamer

Producers describe her character as a "soulful young transgender woman with a fierce drive to protect others."

Maines gained national attention for her battle against her Orono, Maine school district over her right to use the girls' bathroom.

Maine's highest court ruled in 2014 that school officials violated state anti-discrimination law when they required her to use a staff restroom.

It was the first time a state high court concluded that a transgender person should use the bathroom of the gender with which they identify.

Maines has previously appeared on "Royal Pains" and "The Trans List." She also wrote a book titled "Becoming Nicole."

According to a press release from The CW, Nia Nal will be a new addition to the CatCo reporting team. She's described as, "a soulful young transgender woman with a fierce drive to protect others."

"Supergirl" is a part of the network's connected DC Comics TV universe that also includes characters from the shows "Arrow," "The Flash," "Legends of Tomorrow" and "Black Lightening." It returns for Season 4 on Oct. 14.

The Associated Press contributed to this report.