Gemma Arterton had to learn how to be ''bad''.

The actress had to find her inner action hero for her latest role as a crime fighter in new movie 'Hansel and Gretel: Witch Hunters' - which follows grown up versions of the classic children's story characters after they escape the gingerbread house - and while co-star Jeremy Renner is well versed in action films, Gemma had to toughen up.

Appearing on British TV show 'Daybreak', she said: ''Jeremy's a professional and has done all of this stuff before, but that was the challenge for me - to really become bad and brave, and learn how to fight, and learn how to do all of my stunts. I had to do a three week intensive fight [course].

''Stunts are usually ... there's an element of you could always really get hurt, but a lot of it is fear. Once you've overcome that, it's really good.''

Following her star-making turn in James Bond film 'Quantum of Solace', the 27-year-old beauty - who is from a working class background in Kent, south east England - has become one of Hollywood's most sought after actresses, something which she still can't believe.

She said: ''I've got bruises all over my arms from the number of times I've pinched myself. It's incredible. It's a dream.''