The Pardoner’s Tale is composed of two stories: a first-person tale about Gus Howkins, an aging Londoner contemplating divorce, and a third-person narration (the controlling narrative) about Giles Hermitage, an established English novelist, unmarried, who becomes involved with the Chichester-Redferns, a woman and her daughter, while he is working on the story of Gus.

The narrative begins with the character that Giles creates assembling his folding-canoe at an estuary on the coast of Wales. Gus, in his forties, has been separated for four months from his wife, whom he was pleased to catch in an extramarital affair. It provided the occasion for him to break up a boring marriage. He is vacationing alone, hoping for something better.

While canoeing, Gus spots a lovely but apparently dazed young woman sitting behind the wheel of her car on a sandy spit that is being enveloped by the tide. The car is lost to the sea, but not before Gus rescues the woman and brings her back to his rented cottage, where in time they make love. When Gus awakens the next morning, he finds that she has disappeared. He decides to search for her, sensing that the woman would provide remission from boredom.

Meanwhile, Gus’s creator, Giles, takes a break from his writing. On the day his story begins, he is agonizing over Harriet, his lover of seven years, who is at the moment somewhere in the air on her way to Australia with her new husband. Attempting to turn his mind away from Harriet, Giles decides to read three pieces of mail from his enormous pile of correspondence.

One letter is from Helen Chichester-Redfern, a woman who lives along the route of Giles’s daily walks. She knows him from his walks and she has read his novels. She is dying of cancer and wants to talk to Giles about his books, particularly the book he must be working on at the time. Through these talks, she hopes to use the writer’s insights to make some sense of her unhappy life. Grasping at anything to interrupt his thoughts of Harriet, Giles telephones the house and agrees to visit Helen.

It is there that he meets her daughter, Diana, a professional guitarist at age twenty-eight. They begin an affair. With each successive visit, Diana’s mother pushes Giles to discuss his feelings about love and marriage and to explain why his books seem to show an antimarriage bias. Gradually, over a series of meetings, she reveals her own bitterness about her husband’s long-ago desertion. In a deathbed request to which Giles reluctantly agrees, she asks him to take revenge on her husband by writing about a selfish person who comes to a mean end. Her wish is fulfilled in The Pardoner’s Tale, although Giles did not originally plan it that way.

Whether Gus ends well or ill, especially with respect to his erotic involvements, depends on how well Giles makes out with Diana. The resolution of one plot determines the resolution of the other. As the tale develops, Gus learns that the girl he rescued is Julia Delmer, a distressed actress who has fled her television-star husband after witnessing his gross sexual misconduct involving two prostitutes and another man. Julia’s unstable brother, Cliff, and soon the police, get involved when Cliff tries to swindle the husband with fraudulent ransom notes while his sister is away. Gus falls in love with Julia and wants to take her away from her husband, Jake, but this is not easy to do. She is a dependent woman, accustomed to centering her life on the man she married, and she has a sisterly, protective attitude toward her delinquent brother. Besides, Gus has his own problems: an estranged wife who seeks reconciliation and a daughter in nursing training whose good opinion of him means much. By the end, events have taken a sad turn. In Gus’s case, Julia returns to her husband. In Giles’s life, Diana suddenly leaves him for an acquaintance whom he never met. Giles returns to his former girlfriend Harriet, and Gus, brokenhearted, believes that his life is over.