Catherine Holly
Catherine is the main character and the protagonist of this play written by Tennessee Williams. Mrs. Venable's niece, Catherine has tragically witnessed the death of her dear cousin, Sebastian. She feels very upset about this death, and feels like she herself may die as well. In response to her remorse, Mrs. Venable admits Catherine to a psychiatric hospital in which Catherine becomes quite 'insane'.
Mrs. Venable
Described as an old and withered person, Mrs. Venable is the mother of Sebastian. After the death of her son, she becomes close to Catherine because both of them feel so bad about what has happened. She ends up sending Catherine away to a psychiatric hospital. Although her son died, she had a very strong urge to preserve the reputation of him.
Mrs. Holly
A static character, Mrs. Holly's name is never specifically mentioned. She is Catherine's mother, and, although she shows empathy for her daughter, she does not do as much with her as Mrs. Venable.
Dr. Cukrowicz
A young psychiatrist, Cukrowicz is the doctor that Catherine meets once she goes to the hospital. He is young and handsome, but Catherine battles with herself over love because of the death of her cousin. Adding even more to the theme of the play, Cukrowicz is a character that helps support the character of Catherine.