The first book in the critically acclaimed Obsidian and Blood trilogy:

Year One-Knife, Tenochtitlan the capital of the Aztecs. Human sacrifice and the magic of the living blood are the only things keeping the sun in the sky and the earth fertile.

A Priestess disappears from an empty room drenched in blood. It should be a usual investigation for Acatl, High Priest of the Dead--except that his estranged brother is involved, and the the more he digs, the deeper he is drawn into the political and magical intrigues of noblemen, soldiers, and priests-and of the gods themselves...