50 Shades of Grey becomes Britain's best-selling book of all time

Move over Twilight and Harry Potter because there's a hot new book series in town. So much so that it's just earned itself the title of the best-selling British book of all time. We are, of course, referring to EL James' hit trilogy, 50 Shades of Grey.

The news was broken by the book's UK publisher, Random House, who Tweeted saying: "E.L James' FIFTY SHADES OF GREY becomes the bestselling British book of all time! The trilogy has sold over 12 million copies nationwide."

The author herself is quoted as saying: "This is totally unexpected. The whole process has been both extraordinary and rewarding."

In case you've been living in a cave, or emersed in sports of a different kind that don't involve 50 shades of anything, the trilogy documents the relationship between twenty-something Anastasia Steele (described as a plain Jane who frequently bites her lip in a bid to look understated, yet seductive) and billionaire Christian Grey (who wears his trousers handing loosely off his perfect hips).

Its erotic nature and exploration of BDSM has caused quite a stir among critics and fans alike. There's also talk that it's being made into a movie and the role of Christian Grey has become one of the most hotly contented for in Hollywood.

Writer Bret Easton Ellis (of American Psycho fame) Tweeted earlier saying he was no longer writing the script for the movie.

But how did fans react? Here's what a few people had to say on Twitter:

‏@naybethdiaz: :'( 'Fifty Shades of Grey' is UK's best-selling book of all time RT @nmyers89: I mean reallllllyyy though.*weeps into my Harry Potter books*

@DarleneBookNook: Might have to finally read this fifty shades of grey book everyone keeps talking about.

@NataliePalms: It's depressing that Fifty Shades of Grey had become the best selling British book of all time - badly written for people who don't read.

@koreykuhl: The first time I heard "Fifty Shades of Grey" I thought someone had broken into my closet and named my wardrobe.

• Who is your celebrity version of Christian Grey? Take our quiz and find out!
• Casting round-up - who's rumoured to be in the running for the main roles?

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