 It contains a guide to Masonic landmarks in Washington D.C.In 2007, in collaboration with Alice Von Kannon, he wrote "The Templar Code For Dummies", a guide to the medieval Knights Templar, the subsequent mysteries and myths that have surrounded them, and their connections with Dan Brown's The Da Vinci Code.In 2008, Hodapp and Von Kannon published their second collaboration, "Conspiracy Theories & Secret Societies For Dummies", which was required reading in a 2010 course on conspiracy at Harvard University.