In 1947, Stingo moves to Brooklyn to write a novel, and is befriended by Sophie Zawistowski, a Polish immigrant, and her emotionally unstable lover, Nathan Landau. Nathan is constantly jealous, and when he is in one of his violent mood swings, he convinces himself that Sophie is unfaithful to him, and he abuses and harasses her. A flashback shows how Nathan first met Sophie after her immigration to the U.S. when she nearly died due to anemia.