Nicholas Hoult has admitted it can be hard for actors to separate real emotions from their characters when they are playing lovers.
The Jack The Giant Slayer star recently split from girlfriend Jennifer Lawrence, who he met when they starred in X-Men: First Class together, and shared some very close scenes.
Nicholas said: "This is a serious issue for actors the world over. I was having a debate about this with an actor friend of mine.
"It's a very odd thing, because you get cast in these roles, and basically what people are saying when they cast you in this is 'potentially you two could suit each other'.
"And obviously because film sets are very intense places where you spend a lot of time with people and are faking a lot of emotions, I think sometimes people end up believing some of those."
Nicholas stars as Jack in Bryan Singer's new adventure film Jack The Giant Slayer, based on the story of Jack and the Beanstalk.
He stars alongside Ewan McGregor, Stanley Tucci and Eleanor Tomlinson as Princess Isabelle.
Nicholas said of Eleanor: "We got along well, we had fun and we were very clear with Bryan of realising the fact that, as our characters didn't have a whole lot of scenes to develop their relationship, because there's so much going on in the film, we had to really work at those scenes that we did have, so people can see why these two are good for each other, and care about each other."
:: Jack The Giant Slayer is released in cinemas on Friday March 22.