A party girl ruins her life when she falls for a married man.

Call girl Gloria Wandrous wakes up in wealthy executive Weston Liggett's apartment and finds Wes has left her $250 dollars. Insulted by the money which she never takes from men, Gloria, whose dress is torn, takes Wes's wife Emily's mink coat to cover herself and scrawls "No Sale" in lipstick on the mirror, but then orders her telephone exchange, Butterfield 8, to put Wes through if he should call. Later, Gloria visits her childhood friend, pianist Steve Carpenter, in his Greenwich Village apartment, where he chastises Gloria for wasting her life on one-night stands, but agrees to ask his girl friend Norma to lend her a dress. After Gloria leaves, Norma jealously gives Steve an ultimatum: He must choose between her and Gloria. Later that day, while Wes takes the train to the countryside where Emily is caring for her mother, he speaks with his friend, Bingham Smith, who tells him to end his adulterous relationships and return to Bing's law firm instead of working for Emily's family chemical business. Later that day, when Gloria lies to her doting mother Annie, claiming to have spent the night at Norma's, neighbor Fanny Thurber insinuates that Gloria spends her nights in less than virtuous circumstances. That evening, Wes returns home and, finding the lipstick and money, places a call to Gloria, explaining the money was for the torn dress. Later that night during a date with Gloria, Wes advises her to ask a high price for her lovemaking talents, prompting Gloria to jam her stiletto heel into his shoe. She explains that she does not take payment for her dates, but prefers to make her living modeling, claiming that she has been hired to advertise the dress she is wearing at three bistros that evening. Drawn by her fierce personality, Wes follows Gloria to the bistros. After watching Gloria flirt with dozens of men at several clubs, he drives her to Happy's, a run-down motel owned by Wes's middle-aged ex-lover Happy. After sleeping together, Wes and Gloria decide to explore the relationship further. Days later, Norma finds the mink coat in Steve's closet and complains about Gloria. Steve tries to explain that after Gloria's father died, Steve looked after her like a brother, but Norma asserts that she does not want to continue their relationship with Gloria in their lives. While Wes and Gloria disappear together for five days, Emily's mother suggests that her daughter divorce Wes, but Emily thinks he is frustrated by the life her family has handed him and insists she will wait until he develops a life of his own. After Wes and Gloria return to the city, Wes admits that he is married. Gloria, far from being surprised, thanks Wes for the respect he showed her during their trip by calling her by her real name instead of "honey" or "dollface." Later that night, when Gloria tells her mother the truth about being a "slut," Annie slaps her. Gloria, grateful that her mother has finally heard the truth, tells her that she is in love with only one man. Gloria visits her psychiatrist Dr. Tredman and insists that her relationship with Wes has cured her of her need for promiscuity, but Tredman suggests it might not be the complete solution. She then rushes to Wes's apartment building with the mink coat to return it, but seeing the elegant Emily in the entryway, leaves in shame. Meanwhile, Wes asks Bing for a job at the law firm and returns home to find Emily has noticed that the mink is gone. Wes nervously makes excuses and rushes out to search for Gloria at her regular clubs, but finds instead that he is just one in the "fraternity" of Gloria's ex-lovers. Meanwhile, Gloria visits Happy, an ex-vaudeville star, who suggests that her own highlife has been a depressing dead end. When Gloria finds Wes at a bistro the following evening, he launches into a series of drunken insults and taunts her, saying "honey, baby, dollface, kid." Gloria then drives Wes to his apartment building where Emily, spotting them from a window above, watches as her husband throws the coat at Gloria, saying that he would never give the tainted object back to his wife. Gloria, now wearing the mink, later laments to Steve that she has earned the coat, every thread and fur pelt, for all her hours prostituting herself to strangers. She then recounts that Annie's boyfriend Hartley had repeatedly raped her when she was thirteen while her mother was away. Even though Gloria felt intense shame for having enjoyed the attention, she subsequently made a life out of repeating the incident. The next day, when a defeated Wes asks Emily for a divorce, she inquires if he is going to Gloria, reminding him that he left her the previous evening. He explains that he loves Gloria so much that the thought of her deserting him drove him into furious rage. When Norma arrives the next morning and finds Gloria asleep on Steve's couch, he calmly asks Norma to marry him. Later at home, Gloria tells her mother she is starting a new life in Boston, gives the mink to Fanny and leaves in her sports car. Finding out that Gloria is on the road to Boston, Wes drives until he spots her car at a café along the highway. Wes tries to apologize to Gloria by asking her to marry him, but Gloria insists that she is "branded" by his insults. He convinces her to go to Happy's to talk in private, but when Happy greets her with scorn, Gloria speeds away. Wes drives after her, trying to catch up to her increasingly fast pace. While turning to see him follow her, Gloria misses the sign for road construction and hurtles over an embankment to her death. When Wes returns to the city, he tells Emily about Gloria's death and announces that he is leaving to "find his pride" and will someday return to see if it has any value to either of them