Corin Hardy thinks audiences are becoming ''very sophisticated to horror stories''.

The 'Nun' director enjoyed putting jump-scares in his new horror movie but thinks filmmakers need to come up with new ways of keeping the ''audience off balance''.

He said: ''That's just what you're trying to do is keep the audience off balance. Everyone's become very sophisticated to horror stories. And you see, it's very hard to just try and keep someone unsure of what's about to happen next. In a story, and in a lead up to a scare, for me, it's a balance of trying to just keep an overall tension within the story and piece, regardless of whether the scares are going to jump out at you.

''Whether that kind of the overall atmosphere just is feeling more and more ominous. It helps that, if you're feeling on edge and you're starting to grip the seats and get sweaty, and you don't know whether there's going to be a scare or if something's going to come out of the shadows. And then also, it's nice to not do that so that they don't know. Oh God, I thought something was. And something comes from another place.''

And the 43-year-old film director ''had a supernatural experience'' whilst filming the movie.

He told ScreenRant: ''I had a supernatural experience ... I had a run in with a couple of, what I assume were, Romanian ghosts. For real in the Mogoșoaia fortress where we were filming the corridor of crosses sequence ... I was based inside a room off the corridor in the darkness, a sealed room. As I went into the room, I saw a couple of guys I thought was sound guys, and it was very dark, low light. I said hello to them. And then I proceeded to watch the sequence that we were shooting ...

''And then when I finally got the shot I was quite elated, punched the air. And I turned around to see if these two guys had seen the take and there was no one there. No one sitting in the room. No way in our out. And it was a moment which I can only explain genuinely as being some Romanian ghosts.''