EXCLUSIVE: Oscar-winner Allison Janney will play trailblazing feminist lawyer Susan Estrich in Annapurna’s untitled Charles Randolph project about the women who took on Fox News kingpin Roger Ailes and the toxic male culture at the network.

Author and liberal commentator Estrich, who was the first female President of the Harvard Law Review and the first woman to manage a presidential campaign, surprised many by representing Ailes even after a slew of sexual harassment allegations surfaced against him.

I, Tonya and Mom star Janney bolsters an A-List cast which already includes Charlize Theron (as Megyn Kelly), Nicole Kidman (as Gretchen Carlson), Margot Robbie (as a Fox News associate producer) and John Lithgow (as Ailes). Oscar-winner Randolph’s (The Big Short) script has been known as Fair And Balanced but the producers have yet to settle on a title. Jay Roach (Trumbo) directs.

Additional characters expected to be portrayed in the ensemble piece include Bill Shine, Judy Roginsky, Jeanine Pirro, Juliette Huddy, Greta Van Sustenen and James and Lachlan Murdoch.

Annapurna is producing with Theron, Beth Kono, and AJ Dix of Denver and Delilah. Roach, Randolph and Lighthouse Management and Media’s Margaret Riley are also producing. Roach’s producing partner Michelle Graham will executive produce.

Janney is currently lending her voice to MGM’s animated reboot of the Addams Family as Margaux Needler, the family’s arch nemesis. Next up she will star with Hugh Jackman in Bad Education and she recently wrapped on Amazon’s Troupe Zero with Viola Davis. She is repped by Gersh and Thruline Entertainment.