"I was like: 'I love you. Please don't tell me to quit my job!' "

Showrunner Ryan Murphy makes the announcement the same day that the final season of Sidibe's "The Big C" premieres.

Gabourey Sidibe is heading from The Big C to American Horror Story: Coven.

The Oscar nominee (Precious) has been added to the cast of the third season of the FX anthology series, showrunner Ryan Murphy revealed Monday.

"Thrilled to announce Oscar nominee Gabourey Sidibe is joining the cast of 'American Horror Story: Coven,' " Murphy tweeted.

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Sidibe joins a cast that includes new addition Kathy Bates and returning players Jessica Lange, Evan Peters, Sarah Paulson, Taissa Farmiga, Frances Conroy and Lily Rabe.

Details on just who Sidibe will play are being kept under wraps.

Murphy's announcement comes the same day that the final season of Showtime's The Big C: Hereafter begins its first of the cancer dramedy's final four episodes. Sidibe plays Andrea, an aspiring fashion student in the Laura Linney starrer.

While little is known about season three of the witch-themed American Horror Story: Coven, producers said at PaleyFest in March the series would again search for haunted places in America. Murphy previously told The Hollywood Reporter that next year would feature three characters playing real people, including previously announced castmember Bates.

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"It's a really cool story that we've been talking for a couple years, and this seemed to be the year to do it," he said, noting the series will shoot in multiple locations, one of which is New Orleans -- the first time the series has exited its soundstage filming location.

Sidibe is repped by UTA, Principal Entertainment and Felker Toczek.

Email: Lesley.Goldberg@thr.com; Twitter: @Snoodit