Brown’s Angels and Demons is the first in a seven-book series. The series centers on protagonist Robert Langdon, a professor of art history at Harvard University who specializes in religious symbology. These action-adventure novels require Langdon to draw on his considerable expertise in symbology to solve pressing mysteries, and they often involve historical or religious elements. Langdon’s historical knowledge has application in suspense-filled, present-time situations. The action also emphasizes Langdon’s considerable physical finesse, intuition, and resourcefulness.

Common themes and motifs recur throughout the series: Conspiracies within powerful institutions (primarily the Catholic Church and political bodies) and in opposition to them is a frequent plot element, for example, and the series draws on popular assumptions surrounding the Church, the Illuminati, and the Freemasons. Langdon’s skill in semiotics and his historical knowledge means that the plot of each book typically takes place in academic institutions and historical sites, and Langdon’s advanced knowledge is the key to unraveling the mystery of each novel. Langdon is often positioned as a lone man seeking out the truth in defiance of accepted history. As such, some scholars have criticized the series for blurring the line between fact and fiction and promoting an inaccurate view of history that gives credence to unfounded conspiracy theories (Lacy, Norris J.