Eighty-one year-old Dr. Juvenal Urbino del Calle, the District of the Viceroy's oldest and most esteemed physician, examines the naked corpse of his friend and most challenging competitor at chess, Jeremiah de Saint-Amour, who commits suicide by inhaling gold cyanide vapors. Saint-Amour lies stiff and bluish on his cot, beside his Great Dane, who is also dead. Although he is rarely anguished by the deaths of his patients, Dr. Urbino feels an aching in his heart for the death of his old friend. In all of the suicides by cyanide he has seen, this is the first that has not been triggered by a torturous love.
The police inspector expresses doubt that the death was intentional, but Dr. Urbino knows that Saint-Amour's death by cyanide is not accidental. Saint-Amour had worked as a renowned photographer of children, and possessed extensive knowledge of chemicals. As he was making his rounds, Dr. Urbino had discovered a note nailed to Saint-Amour's street door, instructing him to enter and inform the police. Urbino uses his power to persuade the inspector to forgo routine legal procedures so that Saint-Amour, an "atheistic saint," may be buried that same afternoon, on Pentecost. Urbino notes that two unusual events have occurred on this Pentecost: the death of a friend and the silver anniversary of one of his medical pupils.
Dr. Urbino notices an unfinished chess game on Saint-Amour's desk. He sees that Saint-Amour was going to be defeated in only four moves, and thinks that if the death had been criminal, the game would provide a good clue. The inspector discovers an envelope on the desk that is addressed to Dr. Urbino. Inside, Urbino finds eleven sheets with writing on either side. The letter, he tells the inspector, holds Saint-Amour's "final instructions," though it is only half- true. Urbino instructs the inspector and the young medical student to lift a loose tile from the floor, from which they extract the combination to Saint- Amour's strongbox. They do not find as much money as was expected in the strongbox, though there is enough to cover the funeral expenses. Dr. Urbino has an intense desire to share the secrets of the letter with his wife.
Dr. Urbino is an old fashioned man utterly reliant on routine: he still makes house calls, travels in a horse and carriage, distrusts modern medicine, and attends mass each Sunday. During his youth, he had frequented the Parish Cafe, where he had perfected his chess game with his father-in-law and a group of Caribbean refugees. It was through chess that Urbino had met Saint-Amour, for they were worthy opponents.
Saint-Amour's posthumous letter instructs Urbino to travel to an odd location in the old slave quarter of the city. When he arrives at his destination, a ramshackle, unnumbered house, an unfamiliar older woman answers the door. She wears all black, a red rose tucked behind her ear, and reveals to the doctor that she had been Saint-Amour's secret lover for half of his life, and had full knowledge of his plans for suicide. She explains that she had been the one who had played, and nearly defeated, Saint-Amour in his final game of chess.
Saint-Amour had sworn never to grow old, and made the decision to kill himself at the age of sixty. Even during his last months, his lover explains, he had not seemed alive. Loyally, she had followed his every instruction in preparation for his death. "Remember me with a rose," he had told her. She tells Urbino that she will not wallow in mourning, but will sell all of Saint-Amour's belongings and continue living happily in the "death trap of the poor," as she always has. Urbino considers this metaphor and how much the city has changed since his youth; with the abolition from slavery, the city's wealthiest families fell to ruin. After arriving home from Saint-Amour's house, Dr. Urbino is disrupted by servants struggling to catch his parrot, which has escaped and flown to the highest branches of the mango tree.