Aaron Johnson was attracted to the 'Kick-Ass' script because it was different.

The 19-year-old actor admits the movie - which tells the tale of a Aaron's character Dave Lizweski who decides one day he wants to become a superhero - was a "whole new world".

He said: "I never played that kind of role before. I was never really getting mugged or invisible to girls. It was a whole new world I went down.

"I liked the idea of going on the journey and give him new experience in life. He battles with obstacles and enjoying life. I understand that - putting a mask on and taking on the world to be the person he wants to be. Apart from that, he seemed so different from that I thought it would be interesting to do."

The star is drawn to the challenge of different roles, and says his portrayal of John Lennon in 'Nowhere Boy' did bring difficulties.

He said: "I think I'm inspired job to job. That's where the challenge is, 'F**k, how am I going to pull this off? I'm playing John Lennon - What have I signed myself up for?' That's what I find interesting - the challenge."

Earlier this week Aaron admitted the green skin-tight costume he wore in the movie made him look like a condom.

He said: "I always think I looked like a green gummy bear... a 'green condom' is what I get called quite a bit. It was a good laugh."