Belly Conklin is about to turn 16, and she’s headed to her favorite place in the world, Cousins Beach, to spend the summer with her family and the Fishers. Belly’s grown up a lot over the past year, and she has a feeling that this summer is going to be different than all the summers before.

Belly used to count down the days until she could return to Cousins Beach, but with Conrad and Jeremiah fighting over her heart and the return of Susannah's cancer, she's not sure summer will ever be the same. When an unexpected visitor threatens the future of Susannah's beloved house, Belly has to rally the gang to come together—and to decide once and for all where her heart lies.

It's the end of her junior year of college, and Belly's looking forward to another summer in Cousins with her soulmate, Jeremiah. Her future seems set, until some core-shaking events bring her first love Conrad back into her life. Now on the brink of adulthood, Belly finds herself at a crossroads and must decide which brother has her heart. Summer will never be the same...