In Dan Brown’s novel Angels and Demons, this symbol is part of a group of metal branding tools that are used in a series of ritualistic murders throughout the story. The brand itself is an artistic ambigram (a word or other representation that retains the same appearance/meaning even if the physical view is altered) of the word “EARTH”, representing one of the four main elements of traditional science. The Illuminati, a secret society that has for centuries been in conflict with the Catholic Church, kidnaps four cardinals just before Conclave (the procedure by which a new pope is elected) begins and proceeds to publically brand and execute them as revenge for similar killings perpetrated by the church nearly 400 years previously. All the while, a highly dangerous explosive is ticking away beneath St. Peter’s Basilica, and the main character Professor Robert Langdon must draw upon all of his historical and cultural knowledge to solve a series of riddles that will ultimately lead to the secret Illuminati hiding place.

Angels and Demons was originally published in 2000 and is one of Dan Brown’s most popular novels. It is followed chronologically by The Da Vinci Code and The Lost Symbol.