Calista Flockhart Calista Flockhart

Calista Flockhart has joined the expanding cast of CBS's Supergirl pilot, TVGuide.com has learned.

Based on the characters from the DC Comics and adapted for TV by Ali Adler and Arrow/The Flash executive producer Greg Berlanti, Supergirl starsMelissa Benoist as Kara Zor-El, an alien from Krypton who escaped to Earth during her home planet's destruction. Flockhart will play Cat Grant, a self-made media magnate. Kara works as her assistant. The Ally McBeal alums joins recently announced Laura Benanti as Kara's birth mother.

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The project marks Flockhart's first series regular role since Brothers & Sisters ended in 2011.

(Full disclosure: TVGuide.com is owned by CBS.)

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