But her hordes of fans may not realize it's not the first time James has explored her massively popular trilogy from Christian's point of view.
The new book, due out on Christian's birthday, began like the previous three novels, as "Twilight" fan fiction using Stephenie Meyer's original characters, hot vampire Edward Cullen and clumsy innocent Isabella Swan. James wrote about 50 pages as an "outtake" from Edward's point of view for a fundraiser that benefited a charity in 2010 as she toiled in the FanFiction.net "Twilight" community of writers under the pen name Snowqueens Icedragon.
"Some material in the book is drawn from that previous work," acknowledged Paul Bogaards, a spokesman for the Knopf Doubleday Publishing Group that includes the "Fifty Shades" trilogy's imprint, Vintage Books.
The new book, "Grey: Fifty Shades of Grey as Told by Christian," was announced Monday and comes, James said, in response to numerous fan requests that she tell his side of the story. It's what she reportedly said back in 2010, when she first wrote from Edward's point of view to help raise money to fight childhood cancer with other fan fiction writers for the non-profit Alex's Lemonade Stand Foundation.
The so-called "EPOV" pages were auctioned off and distributed to donors.
Switching perspectives is common among some fan fiction writers, who take on a variety of genres and styles while honouring their favourite books, TV shows, movies and other entertainments.
Readers who made it to the end of the third book in the trilogy, "Fifty Shades Freed," already know that she had teased a chapter written from Christian's point of view, included at the back of the book. That chapter covers Christian's infatuation with the virginal Ana through their first meeting — and his stalky encounter with her at the hardware store where she works to pick up some tape, rope and cable ties.
James' "EPOV" fan fiction for the charity follows a devastated Edward after he introduces Bella to his BDSM lifestyle with six hard lashes from a belt in his playroom. She tells him she loves him. He realizes he loves her, too, but she doesn't love the hard-core rough stuff and he insists, "She cannot love a monster," wrote Snowqueens.
It's ground already covered, as the title of the new book suggests. Ana's fleeing of Christian after her belt lashings is how "Fifty Shades of Grey," her first book, and the movie starring Jamie Dornan and Dakota Johnson, end.
In the auctioned-off work, Edward (later renamed Christian by James) visits his therapist to work out post-traumatic stress brought on by the devastating departure of Bella, complete with flashbacks to his violent upbringing as the son of a crack-addicted prostitute who commits suicide.
The therapist asks him if he has considered a, um, more traditional relationship with his young love interest.
"No, I haven't," he responds.
"Because it's never occurred to me that I could," he explains.
The flipped fan fic includes plenty of salty language, lovemaking and F-bombs like the three "Fifty" books. After Bella leaves, Edward decides on a campaign to win her back, but "deep down I wish I had the courage of my convictions. Anxiety unfurls in the depths of my gut. This has to work. She's my only hope," Snowqueens wrote.
The two heatedly reunite after he offers her a lift to the opening of a friend's photo exhibit in a scene that has Edward nearly taking Bella on the spot after they abruptly leave. He restrains himself with this admonishment: "No! No! Cullen! Not like a cheap hooker in an alley."
Over a bite of dinner, Bella confesses that she had forgotten her safe words to shut Edward down during the belt lashings, her test to see if his most certainly not-vanilla sex world might be her thing, too.
It's unclear whether "Grey" will extend the "Fifty Shades" story beyond the three published books or cover old ground from the new first-person approach.
Anne Jamison, an associate professor of English at the University of Utah in Salt Lake City, said the "EPOV" outtakes of James' original fan fiction, titled "Master of the Universe," made for a strong calling card when she went in search of a publisher, based on its popularity as an auction item.
Jamison delved deeply into fan fiction for a class segment she taught on the topic at the time James produced the charity work. Jamison recently taught an entire class on fan fic as a visiting professor at her alma mater, Princeton, after putting out her own book in 2013, "Fic: Why Fanfiction is Taking Over the World."
Meyer herself flipped first-person perspectives from her Isabella to her Edward in "Midnight Sun," an unfinished companion novel to the "Twilight" series that she had planned when a partial draft leaked on the Internet in 2008. Meyer put the partial work on her website for all to read and never released it as a book.
The leak occurred before James fiddled with perspective to provide Edward's take on her own story for the charity event.
James' "Fifty Shades" trilogy has sold more than 100 million copies worldwide. The first of at least three planned movies was a blockbuster that raked in nearly $570 million worldwide. She has acknowledged the books began as "Twilight" fan fiction before she decamped from FanFiction.net to an Australian publisher, then jumped to Vintage.
"We used to laugh about what she'd do for her next book. Well, obviously she's doing EPOV," Jamison said. "I think she's really canny about giving her core readership what they want."
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