The diary of Carolina Maria de Jesus begins on July 15, 1955, the birthday of her youngest child and only daughter, Vera Eunice. Carolina writes that she wants to buy shoes for Vera Eunice, but has no money. Instead, she finds some in the garbage, cleans them and patches them for the little girl. On any given day, Carolina goes for water at a public spigot, and then faces a day that typically involves a search for a way to feed her family. During the day, she usually finds time to write and to read. She says that she intends to fight her way out of the terrible life she lives by selling her writing.

Carolina lives in a "favela" - a ghetto of sorts in Sao Paulo, Brazil. She lives in a shack that she built herself with her two sons, Jose Carlos and Joao, and her daughter, Vera Eunice. She isn't married and never has been, saying that she doesn't need a man in her life. She never mentions the men who fathered the boys but interacts occasionally with Vera's father. The man pays a small monthly stipend for support and to ensure Carolina's silence. Carolina is sometimes angry that he lives in comfort while his daughter lives in squalor, often hungry.

Hunger is the basis of life for those in the favela. On most days, Carolina walks the streets in search of anything that she can use herself or sell for scrap. Sometimes, she finds vegetables that she cooks for her family. She often stops at the slaughterhouse where she begs for bones to boil for broth. Merchants often dump their rotten food in the area around the favela, which is located near the river. Carolina calls it persecution of a sort. By throwing the rotten food where the hungry children can find it, the businessmen are tempting the children to eat food that will make them sick. Carolina once saw a hungry child eat rotten meat. The next day, she found him dead.

The constant search for food tires her and the inadequate diet works against her, but Carolina still manages to make time to follow her dream - becoming a writer. She calls herself a "poetess" and submits her writing to various editors and publishers, eventually earning publication of a book and a newspaper series.

The "Child of the Dark" is the story of her life for part of 1955, all of 1958 and 1959. The reader will journey through the ups and downs as she sometimes finds strength to go on against incredible odds and sometimes loses faith to the point that she says she considers a suicide pact with her children.