Shocking confessions are made as the Red Devil is finally unmasked and the killer revealed.

Chad takes Chanel to his family home for Thanksgiving, where she meets his brothers, Brad and Thad, as well as his parents. However, an uninvited guest throws the holiday into chaos. Meanwhile, Dean Munsch gathers the survivors at Kappa House, but dinner quickly explodes into accusations of who among them is really the killer. Then, the Red Devil carves up a deadly main course as another victim falls.

The Green Meanie sets its final plan for revenge in motion as Hester makes a bold move to secure her future, and Brock performs a dangerous surgery to save Dean Munsch's life.

After the latest attack by The Green Meanie leaves everyone shocked and saddened, Dean Munsch and Denise, along with Hester, devise a plan to catch the killer by throwing a Halloween party in the hospital. Meanwhile, Chanel celebrates a different kind of Chanel-O-Ween and attempts to make contact with the killer’s latest victim from beyond the grave. Once the party begins, an outbreak surprises the hospital, leading Brock and Cassidy to jump into action, and another victim falls.

Shocking confessions are made as the Red Devil is finally unmasked and the killer revealed.

The Chanels are overwhelmed when their TV idol, Dr. Scarlett Lovin, visits the C.U.R.E. Institute. Meanwhile, Hester calls a Green Meanie summit as the killer(s) put their final kill plan into effect.

Determined to find out who the killer is, Dean Munsch, Denise and the Chanels question Hester, as well as the sole survivor (guest star Alec Mapa) of the Halloween massacre. Chad accuses Brock of being the killer and makes a shocking proposal to Chanel. Meanwhile, a new patient with an outrageous disorder (guest star Cheri Oteri) leads Chanel #3 and Cassidy to grow closer, and another victim crashes a celebration.

Twenty years after a mysterious death rocks Wallace University, another murder takes place.

In an effort to secure positive press for the hospital, Dean Munsch pitches a risky surgery to Dr. Holt, whose hand begins expressing more of a wild and dangerous personality than ever before. Meanwhile, Chanel #3 forces Cassidy to undergo a psych test to find the root of his condition with surprising results, and Nurse Hoffel sets a devious plan in motion.

Dean Munsch is left in a desperate situation when a shocking event leads her to come face-to-face with her ex-husband's mistress. Meanwhile, in an attempt to determine who the Red Devil killer is, the Kappas use a Ouija board to communicate with Chanel #2 from beyond the grave and learn of a wicked plot against one of their own.

Chanel finds a new project in Hester, Chanel #3 confesses a secret and Grace and Zayday uncover a surprising connection between two fellow students. Meanwhile, Denise sets her sights on one of the Kappas, and Dean Munsch appoints a new Wallace University mascot as Chad and Earl Grey lead the fraternity on a witch hunt for the Red Devil.

After an influx of patents at the C.U.R.E. institute, Dean Munsch and Chanel organize a blood drive to solve the hospital's severe shortage. Meanwhile, Nurse Hoffel sets a plan of revenge in motion, Hester finds a way to join the hospital's staff and a shocking revelation involving The Green Meanie occurs.

When anti-Kappa Dean Cathy Munsch decrees that sorority pledging must be open to all students, and not just the school’s silver-spooned elite, all hell is about to break loose, as a devil-clad killer begins wreaking havoc across the campus.

Grace enlists Chanel’s help to learn more about KKT’s past, and ends up realizing she might not be so different from her nemesis after all. Dean Munsch goes “psycho” when she becomes the latest target of the Red Devils. Meanwhile, Denise becomes the new house mother of Kappa House and a shocking figure from the past returns.