Abigail Matthews is just thirteen when the stranger arrives at her family's ranch near Gila City, Arizona. But he's only half a stranger to Abigail—he's been appearing in her dreams for weeks. He says she's been chosen by God for a secret, singular task, and an angel has sent him to take her across the territory to the holy place where she can serve her purpose. With faith in her heart, she joins her mysterious stranger, determined to see her calling fulfilled.

The man selected to guard Abigail on her way has his own reasons for accepting the job—Cain, cursed by the Lord to be a fugitive and a vagabond for all time, has spent the past six thousand years wandering the earth with no one but his dog for company. He's ready for his punishment to end, and he's willing to face whatever comes to earn it.

The road they must travel is long and fraught with dangers both mundane and hellish--monstrous demons hunt Abigail at every turn, determined to see her dead before she reaches her destination. Cain himself faces complications much more insidious—shadows from his past lurk just at the edges of his vision, muddling his thoughts and forcing him to question the true purpose of his charge.

If they're to finish their journey, the pair will have to learn to trust in each other—and Cain will have to remember what it means to have someone to protect.