After years of delay and anticipation, Knopf Doubleday Publishing Group will release Dan Brown's "The Lost Symbol" this September with an initial print run of five million copies.

The new novel is a follow-up to the "The Da Vinci Code," the bestselling adventure that sold 81 million copies worldwide. Brown's editor, Jason Kaufman, hinted at a "new landscape" that could confirm GalleyCat senior editor Ron Hogan's suspicion that the book will focus on 2012, the much ballyhooed Mayan date for the end of the world.

Here are Kaufman's comments, from the release: "This book's narrative takes place in a twelve-hour period, and from the first page, Dan's readers will feel the thrill of discovery as they follow Robert Langdon through a masterful and unexpected new landscape."