Sarah Paulson is ready to tell a new horror story.

In Netflix’s new series, Ratched, she stars as Mildred Ratched, years before she becomes the monstrous — yet iconic — Nurse Ratched of One Flew Over the Cuckoo’s Nest. (Louise Fletcher played the role in the 1975 film, for which she won the Oscar.)

“I think people think we’re remaking Cuckoo’s Nest, which we’re not doing. This is a prequel,” Paulson clarified to 360aproko. “It’s sort of an origin story. It’s how that woman came to be.”

Ratched, which hails from Ryan Murphy and longtime collaborator Ian Brennan, sees Mildred arrive in Northern California in 1947 and secure a job at a psychiatric hospital, her inner darkness finding its new purpose amid the world of mental health care.

On Tuesday, during Netflix’s Television Critics Association’s summer press session, the series’ twisted first trailer debuted. Watch now:

During the TCA presentation, Paulson spoke about playing a character she didn’t originate, admitting that it was an “enormous plus” to have the “great fortune” of studying Fletcher’s performance.

“It gave me an opportunity to have a real spine of the character built in,” she told reporters, “in terms of knowing where I was going with it… It’s an imagined idea of what Mildred’s life would have been before she found her way to the hospital.”

“Some people are going to be looking for Louise Fletcher,” Paulson added. “And I don’t want people to be disappointed. It’s a blessing and a curse.”

And while she didn’t reach out to Fletcher or any other surviving actors or producers from Cuckoo’s Nest, she “thought about Louise Fletcher every day.” “I hope in the coming season there will be some Louise Fletcher,” she said.

Alongside Paulson’s titular nurse, the series stars Cynthia Nixon as a politico, Judy Davis as a no-nonsense fellow nurse and Sharon Stone as an eccentric heiress, with Jon Jon Briones, Finn Wittrock, Charlie Carver, Alice Englert, Amanda Plummer, Corey Stoll, Sophie Okonedo and Vincent D’Onofrio rounding out the ensemble.

Ratched premieres Friday, Sept. 18 on Netflix.