As the much anticipated The Lost Symbol hits bookstores, Dan Brown speaks about his latest book  in an interview with The Wall Street Journal.

When asked why there has been a 6-year wait for a sequel to the phenomenally successful The Da Vinci Code, Brown says, “The materials and the ideas are so complicated that it took me a lot of time to process it so that I could use it effectively in a story.”

In another interview with Entertainment Weekly, Brown put it this way, “I will not write a lame follow-up. It could take me 20 years. But I will never turn in a book that I’m not happy with. Four years ago, I wasn’t happy with the book. Five years ago, I wasn’t happy with the book.”