Dan Brown’s novel The Da Vinci Code is a publishing phenomenon. It has sold over 17 million copies, been translated into over 40 languages and topped best-seller lists around the world. It’s also about to be made into a Hollywood movie directed by Ron Howard and starring Tom Hanks as hero Robert Langdon and (possibly) Kate Beckinsale as fellow sleuth and love interest Sophie Neveu. Why has this book caught the imagination of the world? Why has it achieved notoriety amongst certain circles? And why has it spawned a host of explanatory guides, articles and websites?

Firstly – if you haven’t read it and you want to save all the surprises for the book or the film, go and read a different article – there are spoilers aplenty below.

It’s probably best to begin with a quick summary of the book’s specific mythology or back-story, as it is this, in particular, that will be of greatest interest to the fortean reader.