Stephen King put an end to the six-month-old mystery of who penned the bestselling Diary of Ellen Rimbauer: My Life at Rose Red on June 24, when he announced on his Web site (www.stephenking.com) that the credit goes to suspense novelist Ridley Pearson, who also happens to be King's bandmate in the Rock Bottom Remainders. Pearson's identity had been kept hush-hush by Hyperion and corporate sibling ABC-TV to add to the allure of the fictional diary, which tied in to King's television miniseries Rose Red.

The unmasking comes in timely fashion, as Pearson's next novel, The Art of Deception, is set for publication on August 6. The thriller features Lou Boldt, a Seattle police force Lieutenant who has appeared in previous Pearson novels, including Middle of Nowhere and First Victim. On his Web site, King promotes the new book and praises Pearson for his work on the diary, saying, "I couldn't have done better myself."

The Diary of Ellen Rimbauer began creeping up the Amazon.com bestseller list prior to the TV movie's debut last January. The diary entries track a series of eerie encounters at a haunted Seattle mansion in 1909 that transform Rimbauer from the innocent and submissive wife of a wealthy industrialist into a frighteningly powerful and obsessive woman.

Pearson hatched the idea for the book after his publisher, Hyperion president Bob Miller, sent him the script for the miniseries to see if he could come up with a tie-in. "I knew [Pearson] was friendly with King, and I was aware that the screenplay for King's previous miniseries, Storm of the Century, had done well for Pocket Books," said Miller. "Ridley read the script, and noticed that a diary was mentioned repeatedly, so he went to Steve and said, 'why don't I just write the diary?' " By all accounts, King thought it was a great idea.

For Pearson, one of the project's attractions was its Seattle setting. "Seven or eight of my 20 novels are set in Seattle, and it's kind of a favorite place for me," he explained, adding that he relished the challenge of creating a voice for Ellen. Pearson went along with King to the set of Rose Red before a Rock Bottom Remainders show and met with the designer, director and others to gather information that would help him envision the characters' world. "The game here was to take the existing script and write a prequel to it that would explain much of what we would later see [in the movie]," said Pearson, who added that he loves an intellectual puzzle. "I had to come up with lives of these people and what they had been through in order to justify what Stephen was going to put their ghosts through. What a fun game that was."