Fierce twenty-two-year-old Addy hasn't had the easiest of circumstances. Then she runs into Adriel, a half-naked young man with major back burns, kickstarting a series of disasters in her life, mainly her younger brother Reed disappearing into thin air with a strange man. She immediately suspects Adriel is the culprit. After all, Reed's kidnapper had the exact same burn marks on his back.

Adriel, who a few hours ago had been a guardian angel, doesn't know why he is on Earth with a human heart pulsating in his chest. After he sinned, he was sure he would be cast in to Hell. Instead, the wild young woman he stopped for help on the road won't stop questioning him about her missing brother.

Although Adriel claims innocence, Addy doesn't believe him until she comes face to face with Lucifer, the lord of Hell, who has imprisoned Reed. Lucifer awakens the demonic blood dormant within Addy and sends her on a mission to corrupt human souls. His desire: to wage war on Heaven with an army of demon-turned humans.

And not following his plan? That's a sure way to get Reed killed. Against Adriel's objections, Addy must follow through with a job she never signed up for--preying on human souls.