Judith Light has joined the cast of Starz’ upcoming horror comedy “Shining Vale” in a guest-starring role.

The show, which is currently in production in Los Angeles now, follows a dysfunctional family that moves into a house in which terrible atrocities have taken place. Only one person in the family seems to notice the house’s bad energy, though: Pat (Courteney Cox), who at first thinks she’s either depressed or possessed.

Light will play Joan, who is described as Pat’s “Lithium-infused mother,” who has battled mental illness for a long time — and also battled her daughter, who she blames for her mental illness. Joan is vain and hyper-critical and will take any opportunity to try to reclaim her youth or belittle her daughter. Joan may be the most frightening horror Pat faces.

In addition to Cox, “Shining Vale” stars Greg Kinnear, Mira Sorvino, Merrin Dungey, Gus Birney (“Dickinson”) and Dylan Gage.

“Shining Vale” comes from Jeff Astrof and Sharon Horgan, with Clelia Mountford, Aaron Kaplan and Dana Honor also serving as executive producers. Cox serves as a producer producer. Astrof wrote the pilot teleplay, from a story by Horgan & Astrof. The series is produced by Warner Bros. Television and Lionsgate Television in association with Other Shoe Productions, Merman and Kapital Entertainment.

Light, who is best known for her sitcom stint leading “Who’s The Boss” from 1984 to 1992 has an extensive list of television credits under her belt, in addition to being a star of the stage. On TV she has been seen in everything from the early-aughts “Dallas” revival to “Ugly Betty,” “Law & Order: SVU,” “Transparent,” “The Assassination of Gianni Versace: American Crime Story” and, most recently, “The Politician.” She is a four-time Emmy nominee and a multiple Tony winner, include two back-to-back featured actress awards in 2012 and 2013 and the Isabelle Stevenson Award in 2019. Up next she will also be seen in the film adaptation of “Tick Tick Boom.”