She has been working in the showbiz since her childhood but Hollywood star Scarlett Johansson feels that she is ready for more challenging roles after turning 25.

Scarlett, who stars in the upcoming Iron Man 2, first found fame as a lead seven years ago with Lost In Translation, the V magazine reported.

'I'm 25, and for some time I've played these characters who are kind of figuring it out, transforming from young girls to young women. I don't feel like a girl anymore. And I feel like my life and career are on a different path than they had been," said Johansson."There's a lot of road behind me. I feel at this point I really want to do work that is challenging to me. Not to say that I don't look at my job and realize that I'm ridiculously fortunate, and purely an actor for hire. You never forget that it's all so vulnerable," said the actress.