In Buddhist cosmology, pretas make up one of several categories of rebirth. They are best known as "hungry ghosts," pitiful beings with miniscule mouths and bloated stomachs whose state of extreme starvation is a result of stinginess and immorality in a former life.

But they were not always portrayed in this way. Of Ancestors and Ghosts traces the construction of the Buddhist realm of the pretas through narrative literature composed in Pali and Sanskrit in the first millennium of Buddhism's development in South Asia. By exploring issues such as where the departed go after they die, how the living can assist the dead in the next world, and how the departed fits into a karmic cosmology, Buddhist monks used these stories to construct the preta realm and, with it, Buddhist cosmology as we know it today. In the process they established themselves as religious experts concerning the dead. Of Ancestors and Ghosts illustrates the importance of narrative for the construction of religious cosmologies, showing that cosmologies come into formation over a long, cumulative process.

Far from being simple morality tales, preta literature helped develop and articulate Buddhist understandings of actions and their fruits. In the process, these narratives portray ethical cultivation as inherently connected to the cultivation of bodies. As a result, stories about pretas speak to the vast range of embodied experiences in the Buddhist cosmos, including the intersection of human/non-human identity and class, caste, gender, and sexuality. These stories help model and elicit aesthetically informed embodied experiences that are themselves ethically formative. As a result, preta literature highlights the enduring importance of emotions and embodiment on the Buddhist path to awakening.