Moses is a thoughtful, lonely Jewish adolescent living in Paris in the 1960s. Starved for affection due to his family circumstances, Moses seeks to purchase time with a prostitute and befriends a saintly neighborhood grocer who teaches him meaningful life lessons.

Moses lives in a dark, dingy apartment with his father, a disturbingly anti-Semitic caricature of a greedy, money-obsessed Jewish lawyer who treats his son coldly and callously. Too damaged himself to be able to interact with his son in a loving manner, Moses’s father alternates between berating him—notably, by juxtaposing his perceived faults with the supposed virtues of his brother Popol, whom his father claims was taken by his wife upon her leaving the family—and dwelling in tense silence. The novella attributes the father’s behavior to the fact that his wife abandoned him for a lover after Moses’s birth and that his family were Holocaust victims.

Expected to run the household, Moses learns to steal bits of his allowance—intended for household food and supplies only—to set aside for worldly pleasures. Upon forming a friendship with the grocer Monsieur Ibrahim, who insists on affectionately bestowing upon Moses the nickname “Momo,” Moses learns profound life lessons through the man’s simple gems of wisdom, which the latter generally proclaims to be contained in his Koran.