Nwokocha Agbadi is a wealthy and proud local chief. He is enamored with Ona, the daughter of another chief. Although Chief Agbadi has many wives he is determined to have Ona. Ona is a proud and headstrong woman and she refuses to marry Agbadi because she must produce an heir to continue her father's lineage.
Chief Agbadi and his friends go elephant hunting in the monsoons. The chief gets seriously injured during his expedition. He is wounded severely and taken for dead by his friends. Many days later he regains consciousness and wakes up to see Ona by his side. They spend a number of days together and eventually Ona becomes pregnant with Agbadi's child.
Ona gives birth to a baby girl and she names her Nnu Ego, which means twenty bags of cowrie shells. Ona soon dies in labour with her next child who also fails to survive her. Nnu Ego grows up to be a smart and beautiful young woman. She is Chief Agbadi's favorite daughter and he marries her off to a wealthy and influential family. However, her marriage soon grows stale because Nnu Ego is barren and cannot give her husband, Amatokwu, any children. Amatokwu marries another woman who before long produces his heirs.
Nnu Ego is unhappy and dispirited, she becomes frail and morose and so she goes back to her father's house. Chief Agbadi arranges her second marriage to a man from Lagos called Nnaife. Nnu Ego travels from her village to the city to meet him. Nnaife is not her ideal man but she decides that if she can have a child with him then she could perhaps grow to love him. Nnu Ego becomes pregnant but her son dies almost immediately after he is born. This devastates her and she tries to throw herself off a bridge but a villager finds her and manages to dissuade her.
Nnaife loses his job and the two struggle to survive, he eventually gets a job on ship which requires him to be gone for months at a time. Nnaife returns from the ship after many long months to the news of his brothers death and his consequent inheritance of all his brother's wives and children. The youngest wife, Adaku moves to Lagos with her children to Nnu Ego's house, fostering a bitter rivalry in the process.
Over the years Nnu Ego's has given birth to four children and she works hard to put them through school and provide for them. After a rather cruel disagreement with the family Adaku leaves and becomes a prostitute to support herself. Nnaife goes to Idubo to assert his rights and settle his brother's inheritance with his brother's eldest wife but he instead comes home with another wife, Okpo.
Nnu Ego has a difficult time supporting her children along with the children that Nnaife keeps fathering. However, one day Nnaife offers to pay for his and Nnu Ego's son, Oshia's, expensive education. Everybody expects Oshia to complete his education, procure a good job and help raise his younger brothers and sisters. Oshia has other plans for himself which distresses and causes great grief for his family. He wants to study in America and he eventually leaves.
Kehinde, Nnu Ego's third child runs away from home with a Yoruba man. Nnaife is enraged and assaults the Yoruba man's father for which he is sent to prison. Adim, their second son emigrates to Canada. Nnu Ego returns to her father's home alone with both her sons abroad and both her daughters married. She eventually dies a lonely death in the village with nobody by her side.
After Nnu Ego's death all her children come down to Ibuza and hold an elaborate funeral for their mother. The four children set up a shrine for her, so women who want children can pray to her. It is said, however, that Nnu Ego never answers the prayers of the women who pray to her for children.
