Sister Jude Martin is the false main antagonist turned anti-villain/supporting protagonist of American Horror Story: Asylum. She is the stern head nun in charge of administration and discipline at Briarcliff Manor. She is a main character in Asylum portrayed by Jessica Lange. Her character undergoes a major fall from grace, during which her name and title change by the end of the story.
She was thought to be the main villain but this was a cover up to disguise the true main antagonist.
She believes that mental illness is the fashionable explanation for sin. She is dedicated to the management of Briarcliff, hoping to make it a model institution and to atone for past sins. While stern towards her subordinates and those in her care, she is remarkably self-effacing in the presence of Monsignor Timothy Howard, the head of the institution, whom she fantasizes about. She does have a capacity for compassion, indicated by her treatment of Sister Mary Eunice and a suffering Jed Potter. She resents Dr. Arden, both for his dismissal of her faith and the free rein he is permitted outside her purview.