Everyone thinks Sophie's sister, Nell, went crazy. After all, she heard strange voices that drove her to commit suicide. But Sophie doesn't believe that Nell would take her own life, and she's convinced that Nell's doctor knows more than he's letting on.

As Sophie starts to piece together Nell's last days, every lead ends in a web of lies. And the deeper Sophie digs, the more danger she's in--because now she's hearing the same haunting whispers. Sophie's starting to think she's going crazy too. Or worse, that maybe she's not....