On the next episode of American Horror Story: Coven, Fiona (Jessica Lange) but go to great lengths to have eternal youth, even if it means betraying someone she loves.

The synopsis for episode 10 of American Horror Story: Coven was published on Foxfast, revealing numerous details about the events of the episode. The episode will be very centered around Fiona, according to the synopsis.

Fiona takes in Marie Laveau (Angela Bassett) after the voodoo queen's people were slaughtered by Hank (Josh Hamilton). Marie later admits to hiring Hank to decimate the Coven of witches, but Fiona ultimately forgives her, noting that she was just doing what she had to do. Instead, Fiona focuses her hate on her daughter Cordelia (Sarah Paulson) for marrying Hank, who made her turn against Fiona.

As a counter attack, the witches devise a plan to weaken Hank's father Harrison (who they learn is Hank's primary employer) by making his company lose money.

American Horror Story: Coven Spoilers: Cordelia Sacrifices Herself to Protect Fellow Witches? 

Additionally, Fiona tries to out Misty (Lily Rabe) as the next Supreme witch of the Coven by luring her with the latter's idol, Stevie Nicks (guest starring as herself). The girls are all taken by Nicks, except Madison (Emma Roberts), who harbors jealousy at Misty being the new contender for Supreme. Madison then goes to "extreme lengths" in her jealousy over Misty.

Meanwhile, Fiona has become more sick than ever before, and she asks Marie for her secret in prolonging her life. Marie tells her of the terrible price it will cost Fiona. A desperate Fiona makes a "terrible" deal that involves and unexpected betrayal. Considering her renewed animosity towards Cordelia, the deal may involve sacrificing her own daughter for eternal youth.

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American Horror Story: Coven returns for episode 10 on Wednesday, Jan. 8 at 10 p.m. on FX.

Watch a trailer for the next episode of American Horror Story: Coven here: