Why so serious? I could kill to play the role of the Joker in The Dark Knight. I think it is one role which defines acting in its true sense. It has so many layers to it and any actor would love to add a role like this to his portfolio. Also,I would love to do a biopic. The greatest thing for an actor is to transform into someone who has already lived his life,who we have read about and whose pictures we have seen. That is a great challenge.