A new video has emerged which spotlights the late Heath Ledger's Joker "diary" that he used while prepping to make The Dark Knight

We'd heard about such a diary before. Ledger told Empire the following back in 2007: "I sat around in a hotel room in London for about a month, locked myself away, formed a little diary and experimented with voices -- it was important to try to find a somewhat iconic voice and laugh. I ended up landing more in the realm of a psychopath -- someone with very little to no conscience towards his acts. He’s just an absolute sociopath, a cold-blooded, mass-murdering clown, and Chris [Nolan] has given me free rein. Which is fun, because there are no real boundaries to what The Joker would say or do. Nothing intimidates him, and everything is a big joke."In the video, which comes from a documentary series called Too Young to Die, Ledger's father Kim shows part of the diary off. His words are a bit tough to make out, so scroll down for a rough transcription of the clip via Batman News "This was the diary. In order to inhabit his character, he locked himself up in a hotel room for weeks. He would do that. He liked to dive into his characters, but this time he really took it to a whole new level."The hospital scene is interesting because when he was a kid, his sister Kate liked to dress him up as a nurse. He was really funny like that. He also was in the movie. This is a make-up test which was done eight months before. Before the end of the shooting he wrote ‘bye bye’ on the back of the page. It was hard to see this."

Talk to Senior Editor Scott Collura on Twitter at, on IGN atand on