Marion Post (Gena Rowlands) is a New York philosophy professor past the age of 50 on a leave of absence to write a new book. Due to construction work in their building, she sublets a furnished flat downtown to have peace and quiet. Her work there is interrupted by voices from a neighboring office in the building where a therapist conducts his analysis. She quickly realizes that she is privy to the despairing sessions of another woman, Hope (Mia Farrow), who is disturbed by a growing feeling that her life is false and empty. Her words strike a chord in Marion, who begins to question herself in the same way. Shortly after, Marion is at her husband's 50th birthday party. In an embarrassing revelation of her friends, Marion learn that her sex life might not be as spontaneous as some others. On another morning, Marion is to meet her sister-in-law Lynn (Frances Conroy) who is running late. She wants to borrow money for their divorce. Marion's insensitivity is on display. Marion learns in that conversation that her brother, though he respects her, hates her. On another afternoon, she overhears Hope discussing her lost chance at love in the therapist office next door. She reflects on her anniversary party where author Larry Lewis (Gene Hackman), Ken's friend, professed his love for Marion. Then Ken's ex-wife Kathy (Betty Buckley) shows up returning some items and interrupting the celebration by claiming Ken and Marion had an adulterous affair while she was in the hospital having her ovaries removed. Ken has a less than impassioned reaction and escorts Kathy out. Larry renews his pleas, but then accuses Marion of being as dispassionate as Ken. Marion and her step daughter Laura (Martha Plimpton) travel to visit her father (John Houseman). Laura admires Marion but resents the way she handles people in her life. Old photographs spur memories of when she went off to college but her brother Paul (Dax Munna) was forced to work in a cardboard box factory. There is also a photo of her friend Claire with whom Marion has lost touch. As they return to the city, Marion sees Hope on the street and takes off in a foot pursuit. Losing her, she runs into Claire (Sandy Dennis) and her husband Jack (Jacques Levy) exiting a theater. They head off for a drink at a bar where her husband hangs on every word Marion says. Claire is jealous and brings up the past when Claire took the attention of her boyfriend David accusing Marion of subtly flirting with him and encouraging his interest. Claire states this is the reason she withdrew from their friendship. The next day, Hope has nothing to say in the therapist's office. Marion reflect on a poem about a black panther in a case whose only see his way out of the cage was death. Marion begins to see herself as judgmental and putting herself above others. Unable to work, she seeks out her brother Paul (Harris Yulin). He tells her that he feels she is embarrassed by him for pursuing his dreams rather than the paths of success that may have been open to him. However, at dinner that night, a former pupil tells Marion how she changed her life with the lectures in her class. Not sleeping at night, Marion takes a rest in her workspace and has an introspective dream. First, Marion walks into the therapists office and tells the doctor that Hope's issue is she is deceiving herself. The doctor confides that she has been killing herself for most of her adult life. Then her father walks in and begins listing the regrets he has had in his life. Next, she is witnessing a scene played out on stage of her own marriage and the lack of passion in it. Then she chats with Larry Lewis and finds out about his life, his lack of regret and that she has become a character in his book. Then she is to witness her first husband's "suicide scene" in which his death was ruled strangulation. He felt he imparted a kind of strangulation he imparted on her, his former student, with his knowledge and opinions she seemed forced to accept. She comes to realize that, like her father, she has been unfair, unkind and judgmental to the people closest to her: her unsuccessful brother Paul and his wife Lynn, who feel they embarrass her; her best friend from high school Claire, who feels eclipsed by her; her first husband Sam, who eventually committed suicide; and her stepdaughter Laura, who admires her but resents her high-handedness. That night Marion and Ken are out with the Banks, friends of whom they are not particularly fond. When they return home, Marion questions Ken why they don't sleep together any more. That night Marion lies awake and remember when she gave a gift to the professor who became her first husband. She remembered the mask, the only thing she could afford, and how they kissed through it. The next day Marion is in search of an anniversary gift for her husband. She wanders into an old antique store and finds Hope sobbing. She finally manages to meet the woman in therapy as she contemplates a Klimt painting called "Hope". Although she wants to know more about the woman, she ends up talking more about herself, realizing that she made a mistake by having an abortion years ago and that at her age there are many things in life she will not have anymore. When Marion returns to the work space she overhears the conversation between Hope and her therapist where Hope is describing the encounter with Marion and how she met a woman who was really sad though she wasn't in a position where anyone would think she should be. She has led this cold cerebral life without feeling. Hope worries that she will follow the same path toward an empty life if she does not change. Hope recounted to her therapist that in the midst of their lunch, that Marion noticed her friend Lydia. Upon closer inspection she saw Lydia was there with her husband displaying mutual affection for each other. In the other room, Marion begins to cry. She realizes that her marriage to her second husband, Ken, is unfulfilling and that she missed her one chance at love with his best friend Larry At home, Ken hurries Marion to get dressed for their anniversary dinner and presents her with gift. Marion declares she isn't going anywhere. She tells Ken she saw him in the restaurant with Lydia. Ken confesses that their affair was a past thing and quite foolish. Marion says in a way she feels sorry for him because he has been as lonely as she has been, Ken doesn't realize he has been lonely, but Marion takes solace in the fact that at least she has come to recognize it. In the days that follow, Marion gets little work done and walks in the streets. She visited her brother Paul who has chosen to stay with his wife even though they always fight. Marion seeks a clean start with Paul and Lynn. Marion walks with her step daughter and makes sure the pending divorce with her father will not affect their friendship. Marion also goes next door and tell the therapist about the acoustics that allow her to hear his patients. She inquires about Hope but Hope has left treatment and the therapist can't offer any way for Marion to meet her. Marion resumes work on her book without interruption and it goes very well. One day she stopped to read the novel by Larry Lewis in which a character was based on Marion. In it, the narrator came to realize that Helenka (the Marion character) would certainly be loving and passionate if she put down her walls and allowed herself to feel. Marion reflects that, for the first time in years, she feels hopeful.