Will ’39 Clues’ be next Harry Potter?

On Sept. 9, the U.S. publisher of the Harry Potter series will premiere a highly ambitious project with a mystery ending for readers and a couple of puzzlers for the industry: How big is the market for a multimedia story -- and can a phenomenon be conceived by a publisher rather than created by the public?

“The 39 Clues” is a planned 10-volume set about young Amy and Dan Cahill and their worldwide search for the secret to their family’s power. The first book, “The Maze of Bones,” is written by Rick Riordan of “The Lightning Thief” fame and has an announced first printing of 500,000. Steven Spielberg has acquired film rights to the series.

Designed for boys and girls 8 to 12, each book will have a different writer, including such bestsellers as Gordon Korman and Jude Watson. Backed by a multimillion-dollar marketing campaign, “The 39 Clues” also features game cards, a contest with a $10,000 first prize and a sophisticated website that includes games, blogs, videos and thousands of pages of background.

“The word we always used was ‘groundbreaking,’ ” says Scholastic executive editorial director David Levithan. “We wanted to be the first out there to introduce this kind of multidimensional thing.”

A Scholastic team, led by Levithan and including about a dozen editors, thought of the series about three years ago, working from the idea of a treasure hunt. The essential outline, including the ending, was set by the publisher. Authors were asked to fill in the details, taking a thread, as Levithan describes it, and turning it into a blanket.

“It’s a different kind of challenge,” Levithan says. “To use a movie analogy, each director of the Harry Potter films brings their own voice and their own vision to what J.K. Rowling has done. You still feel there’s a consistency there, and part of the fun is seeing what they add to it.”

Scholastic quickly decided that “The 39 Clues,” its title an homage to Alfred Hitchcock’s “The 39 Steps,” would make an ideal multiplatform event. Readers might check out the website, just as kids who love online games might then turn to the books. A recent study by the American Library Assn. revealed that many librarians already use games to attract young people and, ideally, get them interested in books.

“I love the gaming aspect of ‘The 39 Clues,’ ” says Jenny Levine, a digital specialist for the library association. “I could also see a lot of libraries forming ’39 Clues’ clubs the way they’ve had Pokemon clubs.”

Countless bestsellers are made through marketing. But a blockbuster, whether Harry Potter or Stephenie Meyer’s “Twilight” novels, virtually always happens spontaneously.

Harry Potter was a publishing hit that became a worldwide phenomenon. Other children’s franchises, including Clifford and Junie B. Jones, began simply as books and expanded in response to public demand.

“I remember when ‘The Sisterhood of the Traveling Pants’ first came out,” says Beth Puffer, manager of the Bank Street Bookstore in New York. “Nobody knew it was going to be so big. That’s how it works. You need the kids to grab on to a book and tell each other about it.”