When u gets Hurted at everystep in your life and a phycological illness for which people mocks you, your anger on society will increasing with time.But if you have some drawback and some dream to reach a decent Point of life but u cant go for the society system,people's negligenc. But you get a way to get rid of your drawback and you just take it. Then you have nothing to lose.And what do you want to do? Unleash your wrath to the people and society so you can take your revenge. Those people who takes your life as a comdey but thats a tragedy in your life you are carrying it every moment your life. You then stand up like hell and show them your darkside. Thats the "Joker".