For Will Innis and his daughter, Devlin, the loss was catastrophic. Every day for the past five years, they wonder where she is, if she is-Will's wife, Devlin's mother-because Rachael Innis vanished one night during an electrical storm on a lonely desert highway, and suspected of her death, Will took his daughter and fled. Now, Will and Devlin live under different names in another town, having carved out a new life for themselves as they struggle to maintain some semblance of a family. When one night, a beautiful, hard-edged FBI agent appears on their doorstep, they fear the worst, but she hasn't come to arrest Will. "I know you're innocent, " she tells him, "because Rachael wasn't the first... or the last. " Desperate for answers, Will and Devlin embark on a terrifying journey that spans four thousand miles from the desert southwest to the wilds of Alaska, heading unaware into the heart of a nightmare, because the truth is infinitely worse than they ever imagined.