Dakota Johnson says her most challenging sex scene in the Fifty Shades trilogy appears in the latest movie.
Johnson told Marie Claire magazine her hardest scene came when her character, Anastasia Steele, is handcuffed and blindfolded by Jamie Dornan's Christian Grey in the infamous Red Room.
Despite preparing thoroughly to shoot the scene, Johnson admitted that the sensation still came as a shock to her nervous system.
"The most difficult one by far - I think in all three movies - was a sex scene in the third film where I was handcuffed with my arms and legs to the gate," she says.
"It's like a fence thing that comes down. And I was blindfolded. And it was kind of shocking, because I didn't realise that no matter how prepared or rehearsed I was, when your senses are taken away like that, you can't control the way your nervous system will react.
"So it was really tricky to navigate that scene. It was kind of difficult."
Johnson also revealed that even though she's a veteran of the Fifty Shades films, she still finds the sex scenes with co-star Jamie Dornan to be awkward.
She confessed: "It's never easy. It's not casual and it's not fun. It never got easy."
Johnson also thinks the Fifty Shades franchise would have entered the record books if all the sex scenes were shot in one day.
She claimed that because the second and third films were shot back-to-back, they could have entered the Guinness Book of World Records.
Asked about the filming schedule for the love scenes, the brunette beauty explained: "If we could do all of the sex scenes in a day or so, that would truly be in the Guinness Book of World Records.
"A lot of it was dependent on the locations, and because we shot the second and third film back to back, the sex scenes were kind of grouped in all together for the most part. And some were not in those two weeks."