Loni Colbe is too young to say goodbye to her husband, but Kevin has been in a coma for five years. All hope of him waking is gone, and Loni knows the time has come to stop his life support. After his death, she is left wondering if she will ever move on with her life, if she will ever stop feeling the pain of his loss. A year later, she attends her ten-year high school reunion, where she runs into an old friend named Nicholas Hart. She shares her pain with him as well as details surrounding a scuba trip she and Kevin had planned to take together. With Nick's prodding, Loni decides to take the trip without Kevin—and with the company of Nick and a few other friends. Despite the loss of her husband, Loni feels alive under the water of the beautiful La Costa Azul of Mexico. She also feels alive with Nick, but she is hesitant to move on with her life. She's afraid of falling in love for fear of getting hurt again. Will Loni give herself another chance at happiness, or will her feelings of abandonment drown her in blue?