50 facts about Fifty Shades

2: Back then, author E.L. James went by the name of 'Snowqueens Icedragon', and the story was called Master Of The Universe.

3: James decided to tweak the story and take out the vampiric component, so Twilight's Edward Cullen became the dominant billionaire Christian Grey and Bella Swan transformed into the submissive student Anastasia Steele.

4: The Fifty Shades Of Grey trilogy was originally published as e-books and print-on-demand paperbacks by a virtual publisher, before it was picked up and re-released in spring 2012.

5: To date, around 100 million copies of the trilogy (there's also Fifty Shades Of Darker and Fifty Shades Freed) have been sold in 52 languages.

6: The publishers have reportedly boasted that at the height of the book's popularity, two copies of Fifty Shades were being sold every second.

7: The popularity of the erotic books within a certain age group inspired the term 'mummy porn'.

8: The book's subject matter meant, all of a sudden, it seemed perfectly normal to discuss BDSM (bondage, domination and sado-masochism) around the water cooler.

9: Its ambiguous beginnings led to a lawsuit when the movie rights were sold, amid claims that the material was part of the public domain and therefore copyright registrations were invalid. The matter was eventually settled out of court.

10: A bidding war between studios broke out to obtain the film rights in 2012.

11: Mark Wahlberg's production company was one of the first to show interest, but they were "blown out" of bidding when it became too expensive. James decided to go with Universal Pictures and Focus Features.

12: As part of the terms, the writer is said to have made it clear she wanted to retain an element of creative control, and is credited as one of the movie's co-producers.

13: Her fellow producers are Michael De Luca and Dana Brunetti, who previously produced Captain Phillips and The Social Network.

14: American Psycho author Bret Easton Ellis was keen to adapt the book.

15: However, Kelly Marcel, who wrote the screenplay for Saving Mr Banks, was hand-picked to rework it for the screen.

16: Angelina Jolie is said to have been interested in directing the movie.

17: According to sources, Joe Wright, who helmed Pride & Prejudice, was considered, but i n the end, British film-maker Sam Taylor-Johnson was chosen for the job.

18: Taylor-Johnson made her directorial debut with 2009's Nowhere Boy, about John Lennon's younger years and starring her now husband Aaron Taylor-Johnson.

19: The director's admitted there have been numerous creative differences between her and James during production.

20: She and the author are said to have fought over the end of the movie; Taylor-Johnson wanted Anastasia to say 'Red', referring to the 'safe word' mentioned in the books, while James wanted it to be 'Stop'. James apparently won.

21: The budget for the film is estimated to be around 40million US dollars.

22: James' first-choice for Christian Grey was apparently Mr Twilight himself, Robert Pattinson.

23: Model David Gandy has said he was approached, but isn't interested in acting.

24: Charlie Hunnam was cast as Christian Grey in September 2013, but 'scheduling conflicts' apparently meant he had to pull out.

25: Taylor-Johnson has since admitted to Empire magazine that she was aware of Hunnams's anxiety, particularly with regards to filming a potential further two movies.

26: Jamie Dornan, who caused quite a stir as The Fall's resident serial killer Paul Spector, replaced Hunnam in October 2013.

27: Dornan is 32-year-old former Calvin Klein model, who dated Keira Knightley for two years and is now married (to fellow actress Amelia Warner) and a father-of-one.

28: The actor has been reported saying: "I am never going to please all 100 million people who read the book. I'll be lucky if half that number are happy."

29: The role of Anastasia went to 25-year-old Dakota Johnson, the daughter of actors Melanie Griffith and Don Johnson.

30: Other actresses who are said to have been in the running include Imogen Poots, Elizabeth Olsen and Alicia Vikander.

31: The audition material for Anastasia included a four-page monologue from Persona by Ingmar Bergman.

32: Although the books are based in Seattle, filming actually began in Vancouver, Canada, which doubles as the city, in December 2013.

33: However, while the film might not have been shot in Seattle, that hasn't stopped tours popping up in the American city, showcasing hotspots mentioned in the novels.

34: The sex scenes in the book are famously explicit and the movie has been given an 18 certificate.

35: But don't expect too much filth: "I didn't want it to be graphically explicit, and I know that's going to be disappointing to some people," says Taylor-Johnson. "It's the build-up and titillation of touch and sensuality."

36: As part of his research, Dornan visited a sex dungeon, later telling Elle magazine: "It was an interesting evening. Then to go back to my wife and newborn baby. I had a long shower before touching either of them."

37: Dornan won't be completely naked on screen (it was in his contract). He told GQ: "Your dignity's intact as much as it's all tucked away in a little flesh-coloured bag... you tie it up like a little bag of grapes."

38: The director decided to treat the sex scenes like action sequences: "I felt it was really important that each sex scene had a different character."

39: Taylor-Johnson also directed the music video for Earned It, by The Weeknd, which features on the film's soundtrack.

40: The rumour-mill is on overdrive that Dakota Johnson and Dornan don't actually get on that well, which is making the press tour rather awkward.

41: Lookout for Jennifer Ehle (of the Nineties Pride & Prejudice adaptation), as Anastasia's mother Carla.

42: Singer Rita Ora makes her acting debut as Christian Grey's younger sister Mia.

43: Though production ended in February 2014, Dornan and Johnson were called back to re-shoot some scenes in October.

44: Not everyone's a fan of the book. Some campaigners argue it glamorises emotionally abusive relationships.

45: Beyonce's Crazy In Love has been remixed for the movie.

46: When the trailer first launched online in July 2014, it received around 100 million views in its first week.

47: In April 2012, Time magazine listed E.L. James as one of the '100 Most Influential People In The World'.

48: The author has an estimated net worth of around 60million US dollars, and that's set to soar following the release of the movie.

49: As of February 5, 2.75 million cinema tickets have been pre-sold worldwide, with over 475,000 tickets sold in the UK alone.

50: The cast have signed up to do all three movies. Reports are coming in claiming the sequels have been given the green light, though nothing has been officially confirmed as yet.

:: Fifty Shades Of Grey is released on Friday, February 13