Addison Sullivan has been in an accident. In its aftermath, she has memory lapses and starts talking to a boy who keeps disappearing. She's afraid she's going crazy, and the worried looks on her family's and friends' faces aren't helping. Addie takes drastic measures to fill in the blanks and visits the Overton Clinic. But there she unwittingly discovers it is not her first visit. And when she presses, she finds out that she had certain memories erased. Flooded with questions about the past, Addison confronts the choices she can't even remember and wonders if you can possibly know the person you're becoming if you don't know the person you've been.