'All magic is beautiful...and terrible. Do you not see the beauty in yours, nor the terror in mine? You can stop a heart, and I can stop your breath.' 
She is heir to a Sultanate that once ruled the world. He is an unwanted prince with the power to destroy. She is order and intellect, a woman fit to rule in a man's place. He is chaos and violence and will stop at nothing to protect his people.
His magic answers hers with shadow for light. They need each other, but the cost of balance may be too high a price. Magic is dying and the only way to save it is to enlist mages who wield the forbidden power of death, mages cast out centuries ago in a brutal and bloody war.
Now, a new war is coming. Science and machines to replace magic and old religion.
They must find a way to save their people from annihilation and balance the sacred Wheel—but first, they will have to balance their own forbidden passion. His peace for her tempest, his restlessness for her calm.
Night and day, dusk and dawn, the end, and the beginning.