On Halloween night, 13-year-old Ruby disappears in the company of a masked figure. She is never seen again. The only witness is Nell Montague, who is just seven years old. 

Twenty-three years later, Nell is trapped in an abusive relationship and still suffering from vivid nightmares of what she saw. When tragedy strikes, she escapes and attempts to put her past behind her. Then, 13-year-old Emily disappears. 

Haunted by increasingly disturbing visions and helped by a reluctant psychic, Nell must unravel the mystery of what really happened that night, because to save Emily, she must first find Ruby. But to do so, she must question everything she thought she knew about her own childhood, and soon discovers that nightmares don't always end when you wake up.