Dr. Stephen Fleming, a physician who has entered politics and became a minister, lives in London with wife Ingrid and daughter Sally. Their adult son, Martyn, a young journalist, lives elsewhere in London. At a reception, Stephen meets a young woman, Anna Barton, the daughter of a British diplomat and a four-times-married Frenchwoman. Anna introduces herself as a close friend of Martyn's; she and Stephen are instantly attracted to each other. Some time later, Martyn brings Anna to meet his parents at their elegant townhouse and reveals they are romantically involved. The sexual tension between Stephen and Anna is apparent, although Martyn and Ingrid seem unaware. After Anna calls his office, Stephen goes to her flat, where they have sex. The following day, Martyn is promoted and Ingrid arranges a celebratory dinner. There, Ingrid seems suspicious and interrogates Anna about her childhood. Anna says her brother, a year older, committed
suicide over "love" when he was 16. After dinner, Martyn drives Anna home and Stephen follows them. Once Martyn leaves, Stephen enters and tells Anna how much he "wanted to touch her during dinner", leading to them having sex again. Anna describes her brother's death, after he had expressed
incestuous desire, saying "he wanted me all to himself and not to grow up." She says that damaged people are dangerous, and that she hates possessiveness. Stephen's obsession with Anna deepens; on a whim, he leaves a conference in
Brussels to go to Paris, where Anna is spending the weekend with Martyn. While Martyn sleeps, Stephen and Anna have sex in a doorway. Afterwards, Stephen moves in opposite Anna and Martyn, spying on them; he now wants to be with Anna permanently, even if it destroys his family. Anna dissuades him, assuring him that, as long as she is with Martyn he will always have access to her. Visiting Anna's home, Stephen finds Peter Wetzler, her former lover. A jealous Stephen assumes Anna is cheating and, when Peter leaves, confronts her. Anna denies it and recounts that, when she witnessed her brother's suicide, she had fled to Peter and slept with him as a reaction. The Flemings visit Edward Lloyd, Ingrid's father and Stephen's political mentor, to celebrate her birthday. Martyn announces that Anna has accepted his proposal of marriage, which visibly disturbs Stephen. That night, Sally observes him leaving Anna's room. An anxious Stephen lies about it, telling Sally he was talking to Anna about the marriage because Ingrid was upset. Later, the Flemings have lunch with Anna's mother, Elizabeth, who disparages the marriage, saying that Martyn doesn't seem like Anna's "usual type" but noting how closely he resembles Anna's dead brother. Elizabeth notices the strained behavior between Anna and Stephen. She deduces the affair and warns Stephen to end it. Stephen initially complies and ends the relationship. He tries to confess to Martyn and Ingrid, separately, but in the end does not do it. He phones Anna, but hangs up when Martyn answers. Anna sends a key to Stephen's office, with the address of a flat where they can meet. She tells Stephen that she could not marry Martyn without being with him. They meet at the flat and begin another tryst, but Martyn—having discovered the flat by chance—finds them in bed. Stunned, he accidentally falls over a railing to his death. A devastated Stephen runs down the stairs naked and clutches his body, while Anna silently leaves. Stephen's affair is exposed and becomes a media frenzy. An anguished Ingrid questions whether he had ever loved her and tells him she wishes they had never met. Stephen resigns his government position. Meeting Anna's mother, he discovers Anna is staying with her, but he and Anna are silent in their last meeting. Stephen, leaving his wife and daughter, retires to a rented room in a southern European town. In narration, he reveals that he saw Anna only once more, in passing at an airport, and that she had a child with Peter. Stephen stares at a huge blowup on his wall of a photo Martyn gave him of Stephen, Anna, and Martyn together. He ends with a calm note: "She was no different from anyone else." ==Cast==