From the Knights of the Round Table to Indiana Jones, the search for the Holy Grail has proved to be a timeless story. Not only has it set the stage for epic adventures, the Grail was “made to order” for historical suspense thrillers, says bestselling author Nelson DeMille.

Legend has it that the Holy Grail is the cup used by Christ during the Last Supper, and its whereabouts has remained a mystery for more than 2,000 years. DeMille, a history major, has tackled the Grail twice. In 1975 he wrote The Quest, published in paperback by Manor Books. “It was my first big book and it did well,” DeMille tells Show Daily. “I had thought about bringing it back for some time.”

Now he is doing just that with a revised hardcover version of The Quest due from Center Street in September. Publisher Rolf Zettersten says the project took root during a “casual dinner conversation” with DeMille, adding, “We were thrilled to have a major bestselling author giving us a gem from his backlist.”

Zettersten says he originally thought DeMille would do a light edit of The Quest. Instead, “Nelson dove into the project and has become very ambitious about revising it. This wasn’t a shave and a haircut. In essence it has become a whole new book.”

The revision did not include fast forwarding the action to 2013, says DeMille, who had to make sure dialogue and events stayed true to the book’s “1970s time capsule.” Set during the Ethiopian civil war, the plot follows four distinct and determined characters on a “deadly search” for the Grail.

As to revisiting an older work, DeMille says, “It was a good break for me. It was challenging and something different. Every writer likes to know he or she can do something different.” He says his biggest surprise was discovering that “some of the original dialogue was awful and dialogue is my trademark.” He believes publishers should not hesitate to reissue old books, revised or not. “I think a lot of authors would like the opportunity to take one of their earlier books which are good, but not as good as they could do after all the years of working in the trenches. Authors do become better writers.”

DeMille signs copies of the first six chapters of The Quest in the Hachette Book Group booth (1828) today, at 3 p.m.