"Fifty Shades of Grey" producers are making sure that the upcoming movie adaptation will be just as steamy as the sexy bestseller, which means that lead actor Jamie Dornan will appear fully naked in his role as kinky billionaire Christian Grey.

In the erotic novel, Christian Grey spends a lot of time naked, so it's no surprise that the 31-year-old Irishman is set to go full-frontal for his starring role in the film. In addition, his co-star Dakota Johnson will also shed her clothes.

"'Fifty Shades of Grey' producers know they have to make the screen version just as steamy as the novel to make it a success," an inside source told Star. "They can't turn it into a Disney movie."

However, for those who would rather not see all of Dornan's man parts, movie producer Dana Brunetti says that the studio will release two versions.

"We could release the R-rated version, which everyone will enjoy, and then for those fans who want to get a little gritty we could release an NC-17 version a few weeks later," Dana explained according to Hollywood Life.

The erotic romance novel "Fifty Shades of Grey" became an international bestseller and has been translated in 52 languages since its release in 2011. So far, the "Fifty Shades" trilogy has sold more than 90 million copies worldwide in e-book and print, making it one of the fastest-selling book series in history.

"Fifty Shades of Grey" will open in cinemas on Valentine's Day weekend in 2015. The adaptation of the best-selling novel began filming this week in Vancouver.