Cara Buono (Stranger Things) and Mitch Pileggi (The X-Files) have been cast in recurring roles as ancient aliens in the fifth season of Supergirl, The CW series that returns on Oct. 6.

Buono will recur as Gamemnae, an ancient alien, who with others of her kind, have been safeguarding the Earth from the follies of humanity throughout the ages. Gamemnae’s aim is to use technology to subjegate humans. Gamemnae is cunning, witty, ruthless, and always ten steps ahead of her adversaries. Gamemnae’s agenda puts her into conflict with her would-be allies and on a collision course with Supergirl.

Pileggi will recur as Rama Khan, an ancient alien who is able to control the four ancient elements — fire, water, earth, and air. Arrogant and willful, Rama Khan has been entrusted to use his powers to protect the Earth from mankind for millions of years but now his agenda puts him at odds with Supergirl as well as Lena Luthor.

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The two characters were introduced in 2002 in the DC Comics series called JLA, an acronym for the Justice League of America. In the comics their ancient magic and grand schemes are tied to Atlantis, the fabled city that exists beneath the waves of the ocean.

Pileggi, well remembered as FBI Assistant Director Walter Skinner on The X-Files, will also be recurring on the next seasons of American Horror Story and The Rookie. On the film side, he recently shot Axis Sally opposite Al Pacino.

Buono can be seen on the critically acclaimed Netflix hit Stranger Things. Buono recently co-starred opposite John David Washington in the Sundance winner Monsters & Men and was recently featured in Amazon’s The Romanoffs and Lifetime’s remake of The Bad Seed with Rob Lowe and McKenna Grace. She was Emmy-nominated for her work as Dr. Faye Miller on Mad Men.

Pileggi is repped by Pakula/King & Associates and Brillstein Entertainment Partners. Buono is repped by CESD, ATA Management, and Schreck Rose Dapello Adams.