The following version of this book was used to create the guide: Freitas, Donna. The Nine Lives of Rose Napolitano. Penguin Random House LLC, 2021.

In Donna Freitas's novel, The Nine Lives of Rose Napolitano, first person narrator, Rose, struggles to decide whether or not she should pursue motherhood. When her husband, Luke, suddenly becomes desperate to start a family, Rose gets overwhelmed. She refuses to take her prenatal vitamins despite her promise to try for a baby.

Then one day, Luke confronts Rose about not taking the vitamins. The two begin fighting. Rose realizes that her lack of a maternal instinct threatens to define her. The more she thinks about the fight in the days following, the more she tries changing her response to Luke's anger, hoping it will beget a different future life for her.

Throughout the novel, Rose's obsessive returns to the day of the vitamin fight, jolt the narrative back and forth in space and time. The novel’s structure is inspired by these temporal shifts.

The remainder of this summary adheres to a more linear form of explanation.

When Rose returns to the fight again, she realizes that if she does not give Luke what he wants, her marriage may end. Furious that his wife will not submit to his desire, Luke pulls out a large suitcase, shoves his belongings inside, and leaves. Rose gradually must get used to his absence, and her loneliness.

Then one day, Luke calls her. She suddenly feels a surge of hope that he will return. They confess to missing one another. However, near the end of the call, Luke reveals that he has started dating someone new. He has to let Rose go in order to pursue the life he really wants.

In another imagined version of the fight with Luke, Rose sees herself giving in to Luke's dreams. Once she finally becomes pregnant and has a baby, she finds some level of joy in mothering her daughter, Addie. Luke, however, grows distant and detached. Then one night, Rose finds photographic evidence of his affair. Instead of confronting him, she tells her colleague and friend Jill, and the two ransack the apartment in search of more proof. They find nothing.

In another version still, Luke and Rose stay together. They eventually become pregnant. Not long after getting the positive test, Rose starts seeing another man, named Thomas. Though she knows she should not be dating when she is married and pregnant, she is desperate to rebel. Eventually she and Thomas sleep together while Luke is away. Afterwards, she becomes increasingly attached to Thomas. Once she finally tells him she is pregnant, Thomas does not know what to do. Rose becomes convinced she will lose him forever. Despite his initial trepidations, Thomas does not end the affair. They continue seeing each other until after Rose has the baby, and until Rose tells Thomas she must save her marriage. Putting the relationship on hold does not succeed in fixing her relationship with Luke.

In some imagined lives, Rose continues seeing Thomas, and eventually asks for a divorce. In other imaginings, she and Luke divorce before she gets pregnant, and she and Thomas date later on.

Throughout each version of her life, Rose is close with her parents. She learns to rely on them despite their differences. They teach Rose about kindness, grace, and patience.

By the end of the novel, Rose realizes that no matter what she chooses, and no matter which version of her life she lives, she will always experience some combination of loss and love, disappointment and joy. She believes this is true of all lives.