The book is a fictionalized account of the life of Fray Servando Teresa de Mier, a real-life Dominican friar from the 18th century. It follows his numerous escapes from colonial authorities across Latin America and Spain after he delivered a controversial sermon in Mexico City. The narrative, infused with magical realism, portrays Fray Servando's adventures and misfortunes as he becomes a symbol of freedom and resistance against oppressive regimes. His journey is marked by a series of bizarre and fantastical encounters, reflecting the author's critique of totalitarianism and exploration of the themes of liberty, identity, and the absurdity of political persecution.

"Fifth Sun" offers a comprehensive history of the Aztecs based on indigenous texts written in the Nahuatl language. The book challenges conventional narratives derived from Spanish sources, presenting an insightful perspective on Aztec life, culture, and politics from the viewpoint of the Aztecs themselves. Through a detailed examination of these native texts, the book reconstructs the rich tapestry of a complex society, exploring its rise, its interactions with neighboring peoples, and its eventual confrontation with the Spanish conquistadors. This work provides a nuanced understanding of the Aztec civilization by highlighting their intellectual achievements, societal norms, and the internal and external challenges they faced.