When Oakley Nelson loses her older brother, Lucas, to cancer, she thinks she'll never recover. Between her parents' arguing and the battle she's fighting with depression, she feels nothing inside but a hollow emptiness. When Mom suggests they spend a few months in California with Aunt Jo, Oakley isn't sure a change of scenery will alter anything, but she's willing to give it a try.

In California, Oakley discovers a sort of safety and freedom in Aunt Jo's beach house. Once they're settled, Mom hands her a notebook full of letters addressed to her--from Lucas. As Oakley reads one each day, she realizes how much he loved her, and each letter challenges her to be better and to continue to enjoy her life. He wants her to move on.

If only it were that easy.

But then a surfer named Carson comes into her life, and Oakley is blindsided. He makes her feel again. As she lets him in, she is surprised by how much she cares for him, and that's when things get complicated. How can she fall in love and be happy when Lucas never got the chance to do those very same things?

With her brother's dying words as guidance, Oakley knows she must learn to listen and trust again. But will she have to leave the past behind to find happiness in the future?