Well thank goodness for that. According to Charlie Hunnam, who is set to play Christian Grey in the Fifty Shades of Grey film, there is "tangible chemistry" between him and his co-star Dakota Johnson.
It's a good job too. If there are no sizzling sparks flying between the film's two leads, a movie centred around a sexual relationship is likely to fall a bit flat...
"As soon as we got in the room and started reading with Dakota, I knew that I definitely wanted to do it," Hunnam said, "because there was a tangible chemistry between us... It felt kind of exciting and fun and weird and compelling, and so that was it."
So the chemistry is there in the read-through – but what about when he is required to film the movie's explicit sex scenes? It seems Hunnam is pretty confident that he'll have no trouble performing then either.
"My first job was on a Channel 4 miniseries called Queer as Folk. [There were] incredibly explicit sexual scenes with a man," Hunnam said. "I mean, I'm 16 and 17 years wiser now. So if I could do it when I was 18 with a guy, I can certainly do it at 33 with a lady." The man makes a fair point.
Speaking to the Hollywood Reporter at the premiere for series six of Sons of Anarchy, Hunnam also opened up about his initial meetings with the film's director Sam Taylor-Johnson, saying he "felt really intrigued and excited about it" before adding: "I went and read the first book to get a clearer idea of who this character was and felt even more excited about the prospect of bringing him to life."
Charlie Hunnam and Dakota Johnson were cast in the saucy cinema adaptation of EL James' naughty novels last week. Hunnam will play S&M loving millionaire Christian Grey who seduces innocent college graduate Anastasia Steele. The best-selling books follow the couple's increasingly risque bedroom antics.
Since EL James announced the casting decision on Twitter there has been something of a backlash, with dedicated fans calling for different actors to play the story's leads. Might Hunnam's confidence in the pair's chemistry be enough to change their minds?
The Fifty Shades of Grey film is scheduled to hit cinemas on 1 August 2014