21-year-old Thalia Vandergruen is struggling to find both the meaning of love and the meaning of her life. Her mother died soon after her birth and she was raised by her wealthy grandparents, who have long shielded her from the truth about who she really is. Now she desperately wants to break free from her life of privilege. But her long-time boyfriend, Will – the one person she thought she could trust – isn't planning to let that happen.

Meanwhile, Sofi Aguilar, a clairvoyant who is Thalia’s only connection to her late mother, has finally been visited by the ghost she has been longing to see for decades—but who she has also feared the most. At the urging of the ghost, she begins to write Thalia’s story in a notebook with a gold cover. As she writes, events begin to unfold that will change everything for Thalia – and Sofi – forever.

As Sofi predicts, Thalia travels to the darkly mysterious south side of Cuba, to Santiago and a coastal village that holds the key to the mystery of her birth and her mother’s death, as well as the secrets of her mother's friendship with Sofi. While there, Thalia witnesses Will begin to make dangerous plans. She also finds a passion that takes her by surprise in the form of Yahriel, a Cuban dive master who shows her the kind of life she can lead if she's willing to take the ultimate risk of being true to herself.

As Thalia struggles with the choice she must make between the life she never wanted and a life that may never truly be hers, Sofi spools out a story that has been dormant for too long and cannot be contained any longer, a story about life, love, and the one thing that is always true.