The only thing scarier than “American Horror Story’s” third season, “Coven,” could be that Jessica Lange might be leaving the series after the fourth season. The Emmy award-winning actress has signed on to do season 4, but said she doesn’t know what will happen after that.

The actress said she has enjoyed being on the show, USA Today quoted her on Monday. "They've been great parts, and they've allowed me to really do things I've never done before. It's been a real treat for me." When asked about her future on the show, she said she had a contract for one more season of the Ryan Murphy show and added, "Then I don't know what will happen." But she did say that season 4 will be “really exciting.”

Lange, 64, has become a Hollywood A-lister for playing complex, intriguing roles on the show. In season 1, she played creepy next-door neighbor Constance Langdon, whose son murdered his classmates in the early '90s, and after that she played Sister Jude Martin, the nun who struggled to conquer the demons of her past.

Just like the seasons past, “Coven” will have all-new characters and an entirely new plot. “What happened last year is we headed down this dark rabbit hole that got darker and darker and darker and darker. I think there has been an effort this year to not go quite that dark. It’s still about horror, but maybe more psychological this year,” Lange said.

In “Coven” the actress will play a “Supreme” witch descended from Salem who used to mingle with celebrities. Lange said he character “has lived the high life,” according to USA Today. She returns back to New Orlenes to mend her relationship with her estranged daughter (Sarah Paulson), who is head mistress at Miss Robichaux's Academy, and to also hopefully rule the coven again.

Kathy Bates and Angela Bassett will also alongside Lange in the series, which also features Emma Roberts, Gabourey Sidibe, Jamie Brewer and Taissa Farmiga.

“American Horror Story: Coven” will premiere on FX Oct. 9 at 10 p.m. ET.