Fifty Shades of Grey comes out in less than a month, and director Sam Taylor-Johnson is still slaving away to finish the final cut of the film.

Sam Taylor-Johnson wants to make sure that Fifty Shades of Grey is perfect when it hits cinemas on Valentine’s Day 2015.

She and her editor are still working very hard to finish the movie, and in her own words, “I’m literally going out of my mind.”

“I have seen this film over a thousand times and I’m now in a blancmange,” Taylor-Johnson tells Red Magazine, as quoted by The Hollywood Reporter.

Related: Fifty Shades tracking at $45m box office with no help from the tampon scene

But Taylor-Johnson desperately wants the film to be the best it can be. “The nuances within – the tiniest shift, look, blink of an eye – can make all the difference and flip it into the wrong territory,” she says of the editing process. “It’s like walking a knife edge.”

It’s been a wild ride for the Nowhere Boy director, who hopes that fans will appreciate how true to the EL James novel her adaptation stays. Taylor-Johnson humorously says she has “practically eaten” the novel in an attempt to familiarise herself with its content.

She and main actor Jamie Dornan (Christian Grey) have not pulled any punches when it came to understanding and properly depicting the world of BDSM.

“Jamie and I had to sit and meet various dominants and dominatrix, just to make sure we understood that world, so that we in no way portrayed it incorrectly,” Taylor-Johnson explains.

Related: To prepare for Fifty Shades of Grey, Jamie Dornan visited a sex dungeon

Understandably, she has just about reached her quota of Christian at this point. After a long and intense production process, which she likens to stepping onto a bullet train, “I need to get off and breathe and think about something else.”

It’s a dark world to immerse yourself in. We don’t blame her for wanting to step out of the playroom!

‘Fifty Shades of Grey’ hits cinemas on Feb. 13, 2015.