There is only one rule for a vampire – never target your own kind.
The winding streets and alleys of modern-day Edinburgh hold a deadly secret. Disappearances are increasing at an alarming rate and the authorities are helpless to stop them.
Danny, a naïve nineteen-year-old, is plunged headfirst into the frightening and deadly world of the supernatural when his older sister Aurelia is attacked and abducted in front of him. Injured and left with a permanent disability, Danny must hunt for her attacker if he is to discover Aurelia's fate.
Mercy is a six-hundred-year-old loner who is as jaded with the vampire community as she is with humans. However, when a reckless nest of vampires move to Edinburgh and start feeding from the poor and homeless, Mercy becomes increasingly desperate to stop them.
A coincidental meeting unites Danny and Mercy. She needs him to do what she cannot: kill the vampires. He needs her to help him overcome seemingly overwhelming obstacles and become a feared vampire hunter. Together they set off into the unknown with just one certainty: if they fail, not only will Aurelia remain lost, Danny, Mercy, and many of the city's most helpless will die.