“Nancy Drew and the Hidden Staircase” star Sophia Lillis has a new case to crack — the mysterious superpowers growing inside her. The “Stranger Things” and “It” actress has signed on to topline upcoming Netflix YA series “I Am Not Okay With This,” Variety confirms.

Created by Christy Hall and Jonathan Entwistle, the coming-of-age story sees a teenage girl “navigating the trials and tribulations of high school, while dealing with the complexities of her family, her budding sexuality,” and her newfound otherworldly abilities. Hall is writing and Entwistle is directing the adaptation of the Charles Forsman graphic novel.

Filming for the project, which will consist of eight 30-minute episodes, has already kicked off in Pittsburgh, Pennsylvania. “I Am Not Okay With This” is expected to debut next year.

Lillis will reprise her role as Beverly in horror pic “It Chapter Two,” set to bow September 6. She played a young version of Amy Adams’ character, a crime reporter, in HBO’s “Sharp Objects.”

Hall is a playwright whose plays include “The Painted Window” and “To Quiet the Quiet.” In 2017 “Star Wars” breakout Daisy Ridley signed on to star in “Daddio,” Hall’s spec about a woman who makes an unexpected connection with her cab driver. No word on an update on that project. In November 2018 it was announced that she’s adapting sci-fi novel “Hold Back the Stars” and another “Star Wars” star, John Boyega, will topline the pic about star-crossed lovers alongside “Black Panther’s” Letitia Wright