'Supergirl' to End After Season 6

Dean Buscher/The CW

The superhero series, led by Melissa Benoist, will officially wrap up in 2021.

Supergirl is going on one final mission.

The superhero series, which follows the adventures of Superman's cousin, Kara Zor-El (Melissa Benoist), will officially end after the upcoming sixth season, The CW, Warner Bros. Television and Berlanti Productions announced Tuesday.

Supergirl will begin production on the final season at the end of September in Vancouver. Writers and producers are currently developing an exit plan for the series' final chapter, which will consist of 20 episodes.

Supergirl debuted in October 2015 on CBS, where it aired for one season before making the move to its sister network, The CW. It was the third Arrowverse show to premiere on the network in 2016, following Arrow and The Flash. It follows Kara, who was sent to Earth from Krypton as a teenager and raised by the Danvers family, and transformed into a superhero after embracing her powers, becoming National City's protector. 

Benoist addressed the final season with a heartfelt message on Tuesday, shortly after news broke.

"To say it has been an honor portraying this iconic character would be a massive understatement. Seeing the incredible impact the show has had on young girls around the world has always left me humbled and speechless," she wrote. "She’s had that impact on me, too. She’s taught me strength I didn’t know I had, to find hope in the darkest of places, and that we are stronger when we’re united. What she stands for pushes all of us to be better. She has changed my life for the better, and I’m forever grateful."

"I’m so excited that we get to plan our conclusion to this amazing journey, and I cannot wait for you to see what we have in store. I promise we’re going to make it one helluva final season," Benoist ended her post.

Arrow ended its eight-season run in January and with Supergirl following close behind, the Arrowverse will consist of The Flash; DC's Legends of Tomorrow; Black Lightning; Batwoman, introducing Javicia Leslie as Gotham's caped crusader; and the forthcoming Superman & Lois spinoff past next year. 

Season 5 starred Benoist (who announced in March she is expecting her first child with husband Chris Wood), Chyler Leigh, Katie McGrath, Jesse Rath, Nicole Maines, Azie Tesfai, Andrea Brooks, Julie Gonzalo, Staz Nair and David Harewood, with special guest star Jon Cryer. Former series regular Jeremy Jordan returned for a multi-episode arc

In addition to Supergirl, The CW will also be saying goodbye to Supernatural after 15 seasons.

Supergirl will return in 2021 on The CW.

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