Edward and Connie Sumner, who reside in a commuter suburb of New York City with their adolescent son Charlie, enjoy a generally happy eleven-year marriage, despite the fact that they both maintain hectic upper-middle-class lifestyles apart from each other that limit their capacity to spend time together. They chose to leave the city once Charlie entered their life. One day in the city, Connie practically runs into Paul Martel, a younger Frenchman who sells old books. Although she is not looking for anything outside of her marriage, Connie can’t stop thinking about Paul, and despite looking for and receiving validation of the strength of her marriage from Edward, she and Paul begin a passionate affair punctuated by light S&M, about which she feels both constant excitement and guilt. Edward gradually discovers that their marriage is not going well and that Connie’s tales about her day-to-day activities do not line up to the reality. If Edward discovers Connie’s affair with Paul, whom she had previously mentioned to him as the white knight who helped her during a crisis, the questions become what Edward will do, both about Paul and about his marriage to Connie, he who has implied through previous action with someone much less important in his life that loyalty is paramount, and what the consequences of any of his actions will be.