When you turn 14, you are to take a test. The result is your Citizen Number, the two character expression that decides your career, your lifestyle, and your role in society. It can't be changed. No negotiation needed. Because if you follow the laws, you will live peacefully in Mytopia, the city of the fortunate Kaytlin Tamer is numbered. And she doesn't mind. That is, until she meets Hunter Ann Creasy.

Adrian is a stranger to poverty and pain. Then his father is mysteriously murdered, and his life his thrown into turmoil. Less than a week later the king captures Adrian's mother, and she too is murdered. To make matters worse, he seems to have fallen in love with The Demon's Angel, a nefarious thief and assassin, whose beauty is almost as legendary as her cold heart. Winter has never known kindness. Her mother abandoned as a child to die in the streets. But against all odds she survived, growing up to become the notorious Demon's Angel. The streets turned her heart to stone, and without a family her only joy is in killing and seeing the blood of those she hated. But her life goes awry when a boy helps her and puts her in his debt, something of which she will do anything to get out of. Even if that means helping him find and kill his father's muderer. All of this: Winter's abandonment and Adrian's pain, can be traced back to a single slip of paper that the king will do anything to get his hands on. Either because of fate or force, Winter and Adrian thrown into protecting it and a secret that in the wrong hands can devastate humanity.