Focus is set in mid-twentieth century New York, as the Second World War was coming to an end. The chief character is Newman, a Christian man, who is the personnel manager for a large company. Although Newman is much too recreant, he shares his neighbor, Fred's, hostility towards Jews. Fred is intent on dealing with the 'new element' in their neighborhood- Finkelstein, a Jewish candy store owner.
Due to certain ophthalmological difficulties, Newman procures a set of glasses that drastically impacts his external appearance, causing him to be mistaken for a Jew, much to his chagrin. Newman furiously quits his company after his boss tells him that he will be moved to a space where not as many people would see him and that his impending promotion was cancelled. Ironically, at Newman's new company the owner and a large number of employees are Jewish.
Anti-semitism soars throughout the city. Newman marries Gertrude, a woman who has witnessed the mobilization of anti-semitism closely. She used to live with the leader of an organization that assaulted and abused Jews that lived in California. The organization believed that the USA would soon get rid of all the Jews that resided within it. One night, both Finkelstein's and Newman's garbage cans are turned over, which Gertrude recognizes as imminent danger to both Newman and herself. In one instance, Gertrude is falsely identified as a Jew, which deeply disgusts and offends her because she is a Christian.
Both Finkelstein and Newman are persecuted. Newman being timid and reticent in nature is happy to stand back and watch the persecution, whilst still being uninvolved. However, since he is a victim himself, however wrongfully, he has no option but to act.
The anti-semitic organizations and alliances grow and their crusades become increasingly violent and insistent, they are determined to take over the USA. Newman is assaulted and thrown out of a rally that he had convinced Fred and his alliances to conduct. He is thrown out because he is taken to be a Jew. Newman later tries to convince Finkelstein to leave the neighborhood and live elsewhere where he won't have to face this persecution, but Finkelstein adamantly refuses.
Eventually, both Newman and Finkelstein are assaulted in the streets by group of unknown men. The two of them manage to fight the men off. Newman comes to realize that he cannot trust his wife Gertrude to stand by him and he leaves her.
