Game of Thrones alum Turner will play Margaret Ratliff, one of Peterson’s adopted daughters, in the scripted telling of the infamous murder case.
She will feature in the eight-part drama alongside Colin Firth, Toni Collette, Juliette Binoche, Rosemarie DeWitt and Parker Posey.
The series, which comes from Christine director Antonio Campos and American Crime Story writer Maggie Cohn, explores the life of Michael Peterson (Firth), his sprawling North Carolina family and the suspicious death of his wife, Kathleen (Collette).
DeWitt plays Candace Zamperini, Kathleen Peterson’s sister; Posey plays Freda Black, assistant district attorney and prosecutor in the Peterson case; and Binoche’s character is being kept under wraps.
Margaret Ratliff and her sister Marth were adopted by Peterson after their mother Elizabeth Ratliff, a friend of the Petersons, died in Germany, after also being found at the bottom of a staircase. Margaret Ratliff is convinced of her father’s innocence.
The Staircase is written and exec produced by Campos and Cohn, and Campos will direct six of the eight episodes of the show, which is produced by Annapurna Television and HBO Max.
The Staircase started out as a documentary from director Jean-Xavier de Lestrade. It told the story of Michael Peterson, a crime novelist accused of killing his wife Kathleen after she is found dead at the bottom of a staircase in their home, and the 16-year judicial battle that followed. De Lestrade was granted unusual access to the case immediately following Kathleen’s death in 2001 in Durham, NC. Her husband, Michael, a local public figure and successful novelist, quickly became the prime suspect and was convicted.
Turner is represented by CAA and Independent Talent Group.
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