With its multiple first-person perspectives in the form of letters and journal entries, "Three Women" portrays the inner workings of a modern African family as they face common relationships, love, family and social problems. The first part which is set in modern times is narrated through Oyinkan's recollections. It opens with the story of Oyinkan's troubled marriage to Kole as they rush their son Moyo to the hospital after Kole accidentally injures him.
The narrative flashes back to Oyinkan's childhood, growing up in her grandmother's house. On the threshold of adulthood, her precarious world is shattered by the death of her grandmother. Bereft and alone in the world, Oyinkan must go and live with Ibidun, her mother after over a decade without her. Ibidun, a self-effacing "new Nigerian woman" struggles to figure out how to introduce her illegitimate daughter to her new family. Her husband barely condones Oyinkan's presence, and the young girl must learn how to live among half-siblings who do not even know that she is their sister. Finally, driven into the arms of the first man who comes along, Oyinkan elopes with Kole but she becomes gradually subdued by his psychological baggage. Oyinkan's hopes for a fresh start with her young son and husband do not materialize into the happiness she has always longed for. Marriage only further compounds her life, she is compelled to set aside her academic aspirations to care for her son. She feels betrayed when her husband like her grandfather and stepfather has an affair and announces he is expecting a child by another woman.
Oyinkan walks out of the marriage, moves into a house that she inherited from her grandmother, and tries to set up a company. While living in her grandmother's house, Oyinkan finds her grandmother's journals and learns about the intricacies which marked the lives of her grandmother and her mother. She discovers that Aduke, her grandmother had been forced to leave her marital home after she was denounced as a witch. Aduke's journals which open in colonial Lagos, Nigeria in 1924 are written in poor English in the form of journal entries because of her limited level of education. Her language is similar to that used in the New York Times bestseller, The Girl with the Louding Voice by Abi Dare.
The journal entries reveal Aduke as a strong and reflective soul, who is ostracized from her family when she is accused of witchcraft. Her daughter, Ibidun, confused and rebellious is raised to distrust her, but after getting pregnant as a teenager, she is forced to seek out her mother for help. Compelled by circumstances, Ibidun is forced to leave her infant daughter in her mother's care. Aduke and her granddaughter, Oyinkan, two outcasts haunted by the fact that they were born outside wedlock, become so close it appears they merge into one being, governed by seemingly synchronic movements.
Oyinkan tries to reach out to her mother, Ibidun, Aduke's estranged daughter who has struggled to reject everything that Aduke stands for. Ibidun's part of the story is narrated through letters. Some revelations in Ibidun's letter to Oyinkan leave her unsettled because they open up so much of Aduke's life that it begins to haunt Oyinkan as she is forced to confront the relationship between the facts in the journal and the fiction which has shaped the lives of all three women.
Oyinkan cracks after she is raped during the course of starting her company. She decides she will fare better passing for a man and starts crossdressing. This only further complicates her life as Kole, on finding her embracing their son during a fit of drunkenness jumps to the conclusion that she is a man who is having a homosexual affair with the boy. Kole lunges to attack her but the boy gets in the way. This event circles back to the opening chapter where Kole and Oyinkan are rushing their son to the hospital.
