Nicolas Cage was unfamiliar with the 'Kick-Ass' comic.

The US actor - who plays Big Daddy in the movie alongside Aaron Johnson - admits he found the scene where he shot 11-year-old Chloe Moretz unusual, but trusted the instincts of director Matthew Vaughn.

He said: "It was something that crossed my mind a lot, particularly as I really wasn't familiar with the comic book.

"I didn't know what the level of violence would be having read the scripts, but I did feel with Matthew Vaughn that it would be treated in a way that it would go more into the realm of not just animation but more a comic-book approach, as opposed to where you would believe these people are really getting hurt."

The 46-year-old star also admits the film was only successful because of the "zeitgeist" around comic book movies at present.

He told Empire magazine: "There seems to be, and I'm no exception to the rule, in the zeitgeist at this particular time, an obsession with comic books and superhero mythology."

'Kick-Ass' has currently made $66 million at the box office.