A man leaves his mistress to court a happily married woman.

When socialite Callie Brooks decides to divorce her husband Henry, she cheerfully announces her decision at one of the regular weekend house parties given at her Sands Point, New York home. Callie's friend, Helen Robinson, immediately congratulates her on the clever stunt and wishes that she could be as original in finding a way to leave her husband, Joe. Though Helen applauds Callie's announcement, Connie Mills, another guest, tells her husband Jack that she finds the casual treatment of divorce distasteful. While Joe falls ill and retreats to the library, Helen joins her playboy paramour, Tony Minot, on the balcony, where she tells him that their affair must come to an end because their love has "gone cold." Later, Joe accuses Helen of ignoring his needs and being more than just a golfing parter to Tony. Joe's suspicions of Tony also lead him to inform Jack that the roué is after Connie as well. Jack quickly dismisses the thought and expresses his confidence that Connie will remain faithful to him. When Jack's car breaks down, Tony drives the Millses home and joins them for a nightcap. While Jack mixes their drinks in the kitchen, Tony tries to woo Connie, but she resists him and reassures him that she loves her husband. Jack realizes that Tony's sole interest in his home is his wife, so with Connie's approval, he throws him out. On his way out, Tony accuses Jack of cheating on Connie when he had an affair with a Follies girl. Connie overhears the charge, but she believes Jack when he tells her that he is innocent. Callie soon throws another weekend party, but when Jack makes last minute changes in his plans and tells his wife that a business meeting will prevent him from attending the first night of the party, Connie goes alone. After Connie leaves, Helen shows up at the Mills's drunk and ecstatic that her husband has gone to Callie's without her. She celebrates by drinking some more and playing a tune on the piano. As Helen flirts with Jack and begs him not to leave, Connie returns home, having changed her mind about going to Callie's party, and catches her husband with Helen. Jack tries to explain, but Connie calls him a liar and orders him to leave the house. When Joe shows up at the Mills's looking for Helen, Connie listens to his complaints about his wayward wife and scolds him for being too weak to leave her. With no one to turn to, Connie calls Tony and tells him to hurry over so that he can start making good on his promise to make her "loose." While getting drunk with his business associate, Jack calls home and learns from Brandt, his butler, that Connie left with Tony. Instead of going to the party, however, Connie and Tony go to his place, where she seduces the bewildered playboy. They kiss, but Connie breaks into sobs and admits that she is not good at being a "bad" woman. When Connie returns home, she admits to Jack that she was with Tony. Connie and Jack discuss their marriage and agree to allow each other to carry on extramarital affairs until they decide what to do. One day, while sunbathing at the beach, Tony tells Connie that he has reformed and then proposes to her. Connie consents to marry him and tells Jack that she wants a divorce that same evening. Jack relinquishes his claim to his wife, but when Connie overhears him telling Tony that all he wants is what is best for his wife, she realizes that he is truly devoted to her and that she must stay with him because she, too, is devoted to him.