First off hope this is the right place for it.
Ok, so if you havent already seen the film you should stop reading this and go to see it now.
It is I think one of the best films i've ever seen, Heath ledger's Joker makes the film in ways, and no it's not because he's dead or anything, it was genuinely one of the most compelling characters in any film.
One part which made everyone sit up and take notice was (spoiler) when the joker had some mafia guy and he had a knife in his mouth and he says "want to know how i got these scars? well my dad came home and starting threating my mom, now she didnt like this so she got a kitchen knife which he didnt like, so he took the knife, saw me, and grabbed me, took the knife in my mouth and said 'why so serious son? why so serious'" that was so creepy.
Really a must see!