Boaz traces the word voodoo to the United States of roughly two centuries ago and treats it, from the start, as a slur. The term allowed anyone so inclined to compress a whole set of fears about people of African descent into a single utterance: that they were uncivilized, credulous, sexually excessive, violent, even cannibals.

The book follows how public understandings of voodoo shifted over time, fastening onto different religious communities and different practices as ideas about Black people changed. Boaz keeps the emphasis on how tightly those stereotypes were bound up with arguments about race and about human rights.

The evidence comes from material written for general readers: newspapers, magazines, travel writing, and books.