"Dear Sunny: I don't expect you to understand any of this yet, but we'll always have yesterday . . . and today, and tomorrow. Maybe one day you'll figure it out. I never could."

With a supportive family, great friends, and a spot on her high school's swim team, Sunshine "Sunny" Pryce-Shah's life seems perfect. Until the day her popular older cousin Shiri commits suicide. The shocking tragedy triggers heart-wrenching grief, unanswered questions, and a new, disturbing ability in Sunny—hearing people's thoughts.

When Sunny "underhears" awful things about what her so-called friends really think of her, she starts avoiding them and instead seeks refuge with the emo crowd. But when she discovers her new friends' true motives, Sunny doesn't know who she can trust anymore. Feeling like she'll drown in the flood of unwanted voices inside her head, she turns to her cousin's journal for answers. Sunny must figure out how to keep everything from falling apart, or she may end up just like Shiri.