The following version of the book was used to create this study guide: Picoult, Jodi. The Book of Two Ways. Penguin Random House, LLC, New York, New York, 2020. Kindle AZW file.

Dawn McDowell was working toward a doctorate degree in Egyptology when she learned her mother was ill and she had to rush home. A few weeks later, her mother died. Dawn was left responsible for her mother's debts and for her younger brother, Kieran. During that time, she turned to a young man named Brian Edelstein for comfort. Brian suggested they live together after Dawn discovered she was pregnant. He took in Kieran as well, Dawn and Brian married. They settled into life raising their daughter, Meret. Some 15 years later, Meret is smart and loved, but she is often angry and defensive because she is overweight. Kieran is training to be a neurosurgeon and lives on his own. Brian is a college professor, known for his theories of quantum mechanics. Dawn had set aside her goal of finishing her doctorate degree and has become a death doula. She has established a business around helping families get through the process of an approaching death. The services, which include everything except medical care, range from buying groceries to finding counseling to planning the funeral. Her knowledge of how the Egyptians faced death plays a role in her personal philosophies.

Brian admits to being in a compromising situation with his young assistant. Though Dawn believes he did not pursue the woman or take advantage of the situation, she is hurt and rushes to get some time away. When Meret becomes interested in DNA, Brian encourages that by buying her a DNA kit that reveals Brian is not her biological father. Dawn suddenly realizes that Meret's father is Wyatt Armstrong, a handsome but overly-confident fellow student in the Egyptology program. Over the years, Wyatt has become the head of the program. Dawn rushes to join him in Egypt, knowing only that she must tell him about Meret and face up to the past from which she had walked away.

In Egypt, Dawn discovers that Wyatt is still handsome and self-assured. He is on the verge of breaking into a new tomb that he discovered partly because of a discovery he and Dawn made on the site 15 years earlier. Wyatt gets permission for her to be on the site. They spend time working together, focused mainly on the task at hand. When Dawn reveals the details about Meret, Wyatt does not hesitate to fly back to Boston with her. They are involved in a terrible plane crash. Wyatt sees a doctor because of a serious cut. They are planning how to go on to Boston when Dawn collapses. She has a head injury that requires surgery and a hospital stay.

While Meret makes it clear that her loyalty is to Brian, the only father she has ever known, she agrees to meet Wyatt. She is relieved when she sees a childhood picture that shows Wyatt was a heavyset child because it provides an explanation for her own situation and hope that it will resolve as it did for Wyatt. Brian is understandably hurt, but he opens his heart to what Meret needs and allows Wyatt to spend time with them. He even steps back to give Wyatt and Dawn a chance to spend time with Meret.

Meanwhile, Dawn has taken on an unusual task for a client named Winifred Morse, known as Win. Dawn agrees to take a letter from Win to the father of Arlo, Win's deceased son. the man Win loved and lost. He is the father of her son. Win is near death when Dawn returns. She whispers to Win that she found the man. He has lived a happy life. Dawn feels Win was holding on, waiting for this news because Win dies a short time later. Dawn and Meret begin connecting as they have not in recent months. They go to a hair salon where Meret pushes a stylist to take Dawn in without an appointment. Later, with matching hairstyles, Dawn and Meret go for a walk and Meret asks her mother what she plans to do next. While it is clear that Dawn never got over her love for Wyatt, it is also clear that Dawn has built a life with Brian. Both men would accept her, but both come with challenges. As the novel ends, Dawn has come to a decision and reveals that to Meret.