The trailer for "American Alien," the Season 4 premiere of CW's Supergirl, shows Kara Danvers will confront fear throughout the upcoming season.

"Fear," Kara says in the trailer. "No matter how much we believe in ourselves, it never really goes away. I think, 'I'm not afraid of anything.' And then something chases me back down the rabbit hole. But when once we catch ourselves, we have to jump right back out there." The trailer also shows off some new characters set to make their debuts in the coming season.

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Supergirl Season 4 will see the departure of series regular Chris Wood, who plays Mon-El, and Jeremy Jordan, who plays Winn Schott, being reduced to a recurring role. Jesse Rath's Braniac-5 will be upgraded to a series regular for Season 4. Several new actors will join the CW show, including Nicole Maines as the first transgender superhero in DCTV history and former Tron star Bruce Boxleitner as the Vice President of the United States.

Starring Melissa Benoist as Kara Danvers, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen, and Chyler Leigh as Alex Danvers, Supergirl returns for its fourth season Sunday, October 14, at 8 p.m. ET/PT on The CW.

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