On Thursday—Percy Jackson’s birthday—Disney Worldwide Publishing announced that The Son of Neptune, the second installment in Rick Riordan’s The Heroes of Olympus series, will have a three-million-copy first printing, the largest in the company’s history. Leading up to the novel’s one-day laydown on October 4, the publisher is staging an Olympian Week that will include outdoor celebrations in New York City and Los Angeles, seven bookstore events that Riordan will attend, and a presentation of pictures and video clips of the outdoor festivities on the series’ Web site.

On Saturday, October 1, Disney is staging a pre-publication event in Manhattan’s Greeley Square, which will be followed by a similar event the next day at The Grove in L.A. Both will include performances and readings by individuals posing as characters from the series. Fans attending the celebrations are encouraged to get into the Olympian spirit by dressing up as their favorite character.

Between October 4 and 10, Riordan will touch down at the winning venues of a contest the publisher held for U.S. and Canadian bookstores and libraries, which garnered hundreds of entries. His itinerary includes A Whale of a Tale/Mission Viejo Library in Mission Viejo, Calif.; Barnes & Noble in Burlington, Mass.; BookPeople in Austin, Tex.; Books-A-Million in Columbia, S.C.; Indigo in Toronto; Penguin Bookshop in Pittsburgh, Pa.; and Tumwater Timberland Library/Orca Books in Olympia, Wash.

The Son of Neptune will simultaneously be released in hardcover, as an e-book, and in a Listening Library audio version. There are 30 million copies in print in the U.S. of the novels in the author’s three series for Disney-Hyperion: Percy Jackson & the Olympians, The Kane Chronicles, and the The Heroes of Olympus—and the books have been translated into 37 languages. The Lost Hero, the first Heroes of Olympus release, published last year, already has three million copies in print.

“Since the publication of The Lightning Thief in 2005, we’ve seen Rick’s audience grow by the millions,” says Suzanne Murphy, v-p and publisher of Disney Publishing Worldwide. “As soon as a new book releases, inevitably the first question fans ask is, ‘When can we get the next one?’ The Lost Hero offered a tease to fans about the return of Percy Jackson, and that happens on October 4. The anticipation is at a fever pitch.”

In addition to the size of The Son of Neptune’s first print run and Riordan’s impressive sales figures, there was another indication this week of the breadth of Percy Jackson’s popularity. On Jeopardy’s August 15th show, in the category of “What Kids Are Reading These Days,” the demigod was spotlighted. The clue: “In the 4th volume of a series, Percy Jackson & the Olympians must fight ‘The Battle of’ this puzzling place. The answer: What is the Labyrinth?