A woman turns herself into a business tycoon to win her selfish daughter a place in society.

After her second husband, Monte Beragon, is murdered in her beachfront house, Mildred Pierce lures longtime acquaintance Wally Fay to the house and then runs away, leaving him with the body. A short time later, Mildred returns to her Pasadena house to find the police and her daughter Veda waiting for her. At the police station, Mildred describes the events that led to Monte's murder: Four years earlier, Mildred's first husband Bert is making a good living in real estate with Wally, who is his partner. After Bert loses his job, however, he quarrels frequently with Mildred over her indulgent treatment of their daughters Veda and Kay. An especially bitter quarrel drives Bert to leave Mildred for his mistress, Mrs. Maggie Biederhof. Kay is upset by her father's departure, but the older Veda is only concerned with how the family will manage financially. When Wally makes a pass at Mildred, Veda suggests that Mildred marry him so that they can get a new house and a maid, but Mildred rejects the notion. Because she has been a housewife from age seventeen, Mildred is only able to find a job as a waitress, but she works hard and bakes pies for extra income. When the snobbish Veda ridicules her mother for working as a waitress, even though this work has paid for her expensive singing lessons, Mildred decides to open her own restaurant. With Wally's help, she buys a house in Glendale from the Beragon estate and remodels it. One day, when Bert takes the girls to Lake Arrowhead, Monte Beragon, the building's former owner, invites Mildred for a swim at his beach house. Later, Mildred returns home and finds Bert waiting with the news that Kay is seriously ill with pneumonia. After Kay dies, Mildred becomes even more determined to provide Veda with the best of everything. Mildred's restaurant is very successful, and soon she owns a chain of restaurants. In the meantime, after her divorce from Bert, Mildred becomes increasingly involved with Monte, giving him money to support his wealthy, idle way of life, but later breaks off the relationship because she believes that he is a bad influence on Veda. Veda makes a secret marriage with wealthy Ted Forrester, and when his parents insist on an annulment, she falsely claims to be pregnant. Wally negotiates a large financial settlement from the Forresters, but when Mildred learns that Veda lied about her pregnancy, she tears up the check and sends her daughter away. Mildred relents, however, after Veda takes a job as a singer in Wally's nightclub. In order to give Veda the socially prominent life she desires, Mildred then arranges to marry Monte in exchange for a third of her successful business. Monte squanders Mildred's money, causing her to lose her business to Wally. After telling the police her story, Mildred confesses to murdering Monte. The police then question Veda, who admits she shot Monte, with whom she was having an affair, after he refused to marry her. Veda blames Mildred for making her the way she is, but Mildred finally washes her hands of her daughter and rejoins the loyal Bert outside the police station.