The narrator is probably telling this story sometime after 1947, the year of the death of his stepfather, Robert Agadganian, Jr. (Bobby). We are told that if the story "made any real sense" it would be dedicated to said stepfather. The narrator also suggests that there will be some dirty joke-like moments in the story.
We skip back in time to 1928, the year the narrator's mother and father divorce. The following year the narrator's mother marries Bobby. After the stock market crash of 1929, Bobby gets in to the business of buying, selling, and appraising art, and the family moves to Paris. In 1939 the narrator's mother dies and the narrator and Bobby move back to New York City.
The narrator, who goes to art school, has eight teeth pulled, reads massive volumes of books, paints and draws lots of pieces, and is increasingly lonely and disconnected both from Bobby and from people in general. One day, he sees an ad in a Quebec newspaper that catches his eye. This ad is for an art teacher at a correspondence school, Les Amis Des Vieux Maitres ("The Friends of the Old Masters") in Montreal.
He quickly fashions a new identity for himself as twenty-nine-year-old widower from the south of France, where he is very cozy with old family friend Pablo Picasso. His pseudonym is Jean de Daumier-Smith. He sends the letters to the director, M. Yoshoto, from Japan. Yoshoto accepts Jean's application, and in June Jean sets off for Montreal.
Jean arrives on Sunday and begins work on Monday. He is given three students. Two of his students, Bambi Kramer and R. Howard Ridgefield are disappointing. He thinks they lack talent. His third student is a nun named Sister Irma. Jean thinks she's an artistic genius and gets extremely excited. He writes her encouraging her to devote her life to art. He waits breathlessly for the arrival of a new packet of her work. He seems to be rather obsessed with her. On Thursday while looking into the display window of the orthopedic appliance shop beneath the school, Jean experiences a moment of deep loneliness and feels isolated from everyone and everything, even the urinals and bedpans in the window. Afterwards he has romantic fantasies about Sister Irma.
The next day, Friday, Jean gets a letter from the Mother Superior of Sister Irma's convent. Sister Irma's permission to attend the school has been revoked. Jean freaks out and writes letters to his other two students expelling them, and telling them to give up art. He writes a letter to Sister Irma, encouraging her to give up the sisterhood for art. (He never sends it though.) Then he decides to get drunk but has coffee and soup instead. He ponders visiting Irma. On his way home he again peers looks into the shop window. A woman is rearranging the display. When she sees Jean she falls, but gets up without looking back at him. Jean feels the setting sun come rushing at his nose at super high speed. Now the urinals and bedpans look like flowers.
After stumbling around a bit Jean goes home. His diary entry for that day in 1939 says, "Everybody is a nun." He then writes letters reinstating his former students. The art school closes because it doesn't have a license, and Jean joins Bobby for summer vacation before going back to his own art school. He never reconnects with Sister Irma, but does keep in touch with Bambi Kramer, his former student.