The novel is written from the point of view of the protagonist, Taylor Greer and written in first person. However, the second and fourth chapters are showcased from the perspective of Lou Ann Ruiz, whose relationship with Taylor remains a focal point throughout the entire plot.
At the beginning of the novel, Taylor is recognized with her given birth name, Marietta, or her nickname, Missy. She lives in Pittman, Kentucky with her mother, but she feels restless and desires to do something else with her life. She compares her life with that of Newt Hardbine, a friend with a similar lifestyle but who died while the two were still in high school. She reveals that although they were alike in nature when they were small, Taylor turned her life around by getting out of the town on a 1955 Volkswagen that she bought with her own hard-earned money. She bids farewell to her mother and promises to herself to keep driving until her car runs out of gas. The town where she has to stop shall be her new namesake and thus the basis of her new identity.
Her car finally runs out of gas at Taylorville, Illinois and true to her word, Marietta changes her name to Taylor Greer. She keeps on driving until she reaches the middle of Oklahoma and her car breaks down right on a Cherokee property. She takes her car for repair and sits down for a breakfast. When she returns to her car, ready to hit the road, she has an encounter with a Cherokee woman who places a baby in the front seat Taylor’s car, introducing herself as the aunt of the baby. She leaves in a pickup truck without giving Taylor an opportunity to protest, who, in a resigned manner, takes the baby with her. While bathing the baby girl, Taylor realizes that the child has been sexually abused and does not speak at all. Taylor names the child Turtle in respect of her inclination towards being attached to objects without letting go of it easily, just like a mud turtle.
The duo makes it to Tucson, Arizona on the broken down car, which Taylor takes to a repair shop to get it fixed, a shop called Jesus is Lord used Tires. The owner is a generous woman named Mattie who takes a liking to Taylor and Turtle. She is shown to ultimately hire Taylor to work at her shop since due to the various car problems, they would have to be staying in town for a longer period of time anyway.
After living in a hotel for some time, Taylor seeks to rent a room, which is how she meets a woman named Lou Ann Ruiz. The narrative shits from Taylor to Lou as more about her backstory is revealed. She is also from Kentucky and is a recently turned single mother to her young son, Dwayne Ray, after her husband leaves them shortly after the arrival of Taylor and Turtle. The two women form a strong bond of friendship having both been, although in different circumstances, rendered single parents to infants.
Since Taylor had already quit her first job at Tucson, she has to work for Mattie at the repair shop in order to pay for the rent of her room. She discovers that Mattie’s shop is a shade for refugees from Guatemala who reside in her home that is located right above the shop. In the process of working for Mattie, she ends up befriending two such refuges named Estevan and Esperanza. Meanwhile, Lou Ann is in shambles when her husband, Angel, makes it clearly knows Lou Ann’s marriage that he is leaving her and their son.
tries to bond more with Turtle and takes her to a doctor to lean more about her situation. The doctor estimates Turtle’s age to be around three years although she looks like an infant due to a stump in her growth. He voices Taylor’s own suspicions about Turtle’s history: she had been physically and sexually abused, causing her to stop growing as well as speaking.
When Esperanza attempts suicide, Taylor learns more about her and Estevan’s past when he himself shares the story with her. They were both involved with the union back in their country and had a child together with the name of Ismene. When the government tried to blackmail them into giving the names of seventeen union members by kidnapping their daughter, Estevan and Esperanza decided to sacrifice their time with Ismene rather than give up the lives of those seventeen people. Thus, they had to flee to the States in order to escape their government. As Estevan spends more time with Taylor while Esperanza gets better, Taylor starts to fall in love with him but does not express her feelings to him.
In the absence of a male breadwinner, Lou has to take up a job in order to support herself and her son. She gets hired at a salsa factory and just as she is starting her new life as an independent single mother, she receives a letter from Angel who has changed his decision and wants her and Dwayne back in his life. He offers a package filled with gifts for his wife and son as a token of apology and requests them to move in with him in Montana. He even offers to move back to Tucson if she will unwilling to make the sudden transition. Lou Ann thinks hard about the matter and afterwards decides that she does not want Angel back in her and her son’s life after his desertion.
Taylor, too has become settled in her maternal role towards Turtle, who has finally started to speak due to the endless support and love she has received from Taylor. One night, Taylor leaves Turtle with Edna Poppy, a blind woman who offers to baby-sit the child while Taylor visits the desert with Mattie, Esperanza and Estevan to experience the first rain of the summer. Edna, who is also a neighbor to Taylor and Lou Ann, takes Turtle to the park for a quick stroll. In the park, a sudden stranger attempts to grab Turtle and sensing an attack, Edna tries to protect the child by using her cane to hit the attacker. Although Turtle is not physically hurt from the incident, she is sufficiently traumatized by the incident and stops speaking again, withdrawing to the same shell she was at the beginning of the novel.
Things only seem to get worse when Taylor is made aware of her lack of a legal relationship with Turtle by a social worker. If Turtle is found to have no relatives, this makes her a ward of the state until she comes to an age of eighteen. Taylor, who has by now formed a true bond of love with Turtle and considers herself to be the mother of this child, is determined to make sure that no one is able to take away her daughter from herself. The social worker advises Taylor to take the legal support of a lawyer in Oklahoma, where the laws may be in support of Taylor should she be willing to adopt Turtle as her daughter.
Taylor and Turtle, along with Esperanza and Estevan who cannot stay in Arizona anymore due to the sudden strict laws regarding illegal immigrants, drive down to Oklahoma to escort the couple to a safe house while also to find Turtle’s legal guardians. She would then attempt to convince them to sign Turtle over to her so she can legally adopt her.
However, this proves to be a futile attempt since she is unable to find Turtle’s relatives, an act made harder due to Turtle’s reluctance in helping Taylor find more about her family. It has been seven moths since that woman had put Turtle on the front seat of Taylor’s car and the locations around the site have changed.
Taylor devises a new plan to keep Turtle to herself. She introduces Esperanza and Estevan as the real parents of Turtle to the legal advisor whose number she had been given to by the social worker. Mr. Armistead is convinced, especially after observing the tear-strewn eyes of Esperanza who is mourning the loss of her own daughter who is of the same age as Turtle. She and Estevan both consent to give Turtle off to Taylor since they are unable to care for their own daughter. The legal papers are prepared and Taylor is officially stated as the mother to Turtle. They safely leave Esperanza and Estevan at their new house in Oklahoma and Taylor has to say goodbye to Estevan. On the way home, Turtle begins speaking again after the assault at the park; she calls Taylor her mother. As a humorous sense of irony, she also starts naming her family members although it is not necessary anymore now that the legalities have been sorted out. They both look forward to their life in Tucson, Arizona and Taylor Greer has finally found her home, her identity and her family, Turtle.