The hospital-themed season will continue the story of the sorority massacre, said The Hollywood Reporter.
"This is the first we're revealing this much of the cast. We're all coming back," Curtis, who will reprise her role as Dean Cathy Munsch, said.
Co-creator of the show Brad Falchuk said the sorority massacre will also take an interesting turn into a fresh setting.
"Dean Munsch has taken her passion for education and brought it into the healthcare system. She has purchased a hospital. All of the girls will be medical students under the rule of Munsch and three hunky doctors," Falchuk said.