The cult of human sacrifice is a pervasive theme in this study. It is a concept that permeated Aztec mythology and was the central preoccupation of the aggressive Aztec state. Another particularly interesting belief explored here is the “mask pool,” whereby gods could exchange regalia and, thus, identities. This vivid and eminently readable study also covers the use of hallucinogens; cannibalism; the calendars of ancient Mexico; tlachtli, the life-and-death ball game; the flower wars; divine transfiguration; and the evolution of the war god of the Mexica. A splendid introduction to Aztec religion, The Fifth Sun also contains insights for specialists in ethnohistory, mythology, and religion.