Yesterday, Ryan Murphy announced that Stevie Nicks would be guest-starring on American Horror Story: Coven. Today, he explains to EW exactly how that will work. She'll play herself in the tenth episode (which airs in January), he says. "It's part of Fiona’s [Jessica Lange] ruse in that Fiona is trying to get the true Supreme to reveal herself because she needs to stay alive," Murphy says. "So she tells Misty Day [Lily Rabe] that the Supreme gets so many great things in life, like tickets to the Oscars and Met Ball tickets. So she brings Stevie Nicks in as a gift to Misty to prove to her that if she exhibits more power she’ll get that and more." Ah, Met Ball tickets, the dream of any witch. "Then the other girls come home and see Stevie and Misty singing and it starts them trying to move much quicker to prove that they are the Supreme," Murphy says. So yes, Nicks will sing, but no, it sounds like it won't be with Patti LuPone.