Make sure to check the pages because I think there are already a few threads like this. Oh well, movie was awesome and Heath Ledger made it excellent.
I really dont see why he over dosed...
He did not OD on purpose. He put himself in a dark room for a month before the movie. He was also taking depressant pills. When he was done acting, doctors immediately put him on anti-depresants and it was too much. Ledger was also drinking alcohol with the pills.
I think it was sleeping pills not anti-depresants and he toke too many because he was having nightmares from playing the part. but he was drinking but I do think he made the movie great.