Courteney Cox starred in one of television's most popular sitcoms and another that became a cult favorite. But she will be the first to tell you that, these days, people haven't exactly been clamoring to get her to do their TV shows.

So when she got her hands on a script for a new TV show, "Shining Vale," about a woman in her 50s trying to rediscover herself, the 57-year-old "Friends" star picked up the phone to pitch the perfect actor for the role: Courteney Cox.

In the horror-comedy Starz series, which premieres Sunday, Cox plays the central figure, Pat Phelps, a former wild child and famous author who is struggling to complete her second novel and grappling with a marriage on the rocks. (Greg Kinnear plays Pat's husband, Terry, and Mira Sorvino plays a ghost who only Pat can see.)

Pat isn't quite sure whether she's depressed, possessed or both. The emotional tenor pushed Cox as an actor in ways she hadn't explored before.

"To play someone who's going through all this emotional stuff gave me so many opportunities," Cox says. "Some of the best acting moments of my whole career came from this show."

Raised in Mountain Brook, Ala., a suburb of Birmingham, it was hard for Cox to fathom a career as an actor. She studied architecture at Mount Vernon College in Washington, D.C., before dropping out and moving to New York, where she worked at a music agency and did some modeling and the occasional commercial spot.

She'd go on to land early roles in "The Love Boat" and "Ace Ventura," but what stands out about that time, she says, is that she didn't know what kind of actor she wanted to be.

"I didn't have the confidence to stretch myself, to push myself," she says. "When I was starting out, I just wanted to get a job. Now, I want to be respected. And I want to be seen as somebody who has been around for a long time and is challenging themselves ... as opposed to we know her."

Cox has been famous for nearly four decades, after all, garnering attention with her appearance in Bruce Springsteen's 1984 "Dancing in the Dark" music video and a run on "Family Ties" before her career took off with her starring role as uptight chef Monica Geller on "Friends."

Three years after "Friends" ended, she executive-produced and starred in FX's two-season drama "Dirt," where she played the editor-in-chief of a glossy tabloid magazine. She had a longer run as divorced single mother Jules Cobb in "Cougar Town." She starred in all five "Scream" films as cutthroat reporter Gale Weathers. Recently, she executive-produced three seasons of the Facebook Watch docuseries "9 Months With Courteney Cox."

But it's "Shining Vale" that has helped her to find a new excitement. "It's been a while since I acted on this scale," says Cox, who is seeking a certain balance, embracing the legacy of "Friends" without being constrained by it.

"I want to be remembered as Monica," she says. "But I'd also like to have something else. ... I want to make a mark not just as one character but as other characters and other successes. I have a lot more to do. I have a lot more to show."