John Langdon (typographer) Langdon is known mostly through his association with Dan Brown, and the novels "Angels & Demons", "The Da Vinci Code," "The Lost Symbol, Inferno, and Origin". The protagonist of these novels was named Robert Langdon as a tribute to John Langdon, and he will continue to be so for his next 12 books, an estimate given by Dan Brown himself. Langdon is now a professor of typography and corporate identity at Drexel University in Philadelphia. He continues to do work on ambigrams, as well and fine art works that incorporate language, type, and philosophy. Langdon credits his paternal grandparents for
Robert Langdon (book series) himself. In the book series, Langdon is himself an author of six (fictional) books: In the real book "The Lost Symbol" on page 8, a minor character, Pam, refers to the (fictional) "Symbols of the Lost Sacred Feminine" as creating 'a delicious scandal'. The series has sold over 120 million copies. The novels were a success around the world and became bestsellers, and soon adapted into films in which Ron Howard directed and produced 3 of 5 novels: "The Da Vinci Code" (2006), "Angels & Demons" (2009), and "Inferno" (2016), with Tom Hanks portrayed the lead character, Professor Robert Langdon,