With reporting by Josh Horowitz.

"Fifty Shades of Grey" is under a lot of pressure to perform at the the box office, and no one is feeling the heat more than producer Dana Brunetti, who helped adapt the NSFW book for the big screen.

MTV News caught up with Brunetti on the red carpet before Sunday night's Golden Globes, and he thinks "Fifty Shades" fans are going to be "pleasantly surprised" with the film.

"The issue of doing an adaptation of a book is the theater of the mind, and so you always face that," he said. "This is the fourth book that I've adapted, and you always face that criticism. Somebody sees it in their head when they're reading it differently than the way you did on the screen, so you always want to get as close as possible to what you think is the best version that's going to meet the fans' expectations. I think they're going to be pleasantly surprised with what we've done with the film."

The producer also opened up about the film's "unusual" R rating, and he's just as confused by it as you are.

"I have no idea what they're referring to. I'll be interested in hearing what everybody thinks the unusual behavior is, but first, when I saw it, I was like, 'Did they do something different to the film since the last time I watched it?' But either I'm too used to it, or it's just unusual."

And just in case you're holding out hopes for a NC-17 version of the sexy flick, you can watch Brunetti quash your fantasies in the video above. (There's always the DVD extras!)

"Fifty Shades of Grey" writhes into theaters on February 13.