Take a Look at Heath Ledger's 'Dark Knight' Diary

It's a pretty uncontested fact that the late Heath Ledger delivered something insanely special when portrayed The Joker in Christopher Nolan's "The Dark Knight."

Filling a crazed pair of shoes previously occupied by Jack Nicholson is no small feat for anyone, but Ledger managed to meet and well exceed all expectations for the twisty character and even went on to (deservedly) receive a posthumous Oscar for the wild performance. And there's a reason he was so good in the role: he worked his britches off to prepare.

In this video excerpt from a German documentary series called "Too Young to Die," the actor's father Kim Ledger introduces the world to the little-known diary he kept while readying himself for the movie.

"He pretty well locked himself up in a hotel and ... galvanized the upcoming character. That was typical of him, really," Kim Ledger, father of the late actor, explained as he thumbed through the pages.

Among the visual inspirations collected in the book were playing cards, comic snippets, character shots from "A Clockwork Orange" and a photo of a laughing hyena ... which, if you think about it, makes a lot of sense. On the last page, Heath simply wrote "BYE BYE." Sob.

Pretty awesome thing to share with the world, right? In pseudo-poker terms, he was absolutely one of a kind.

[caption id="attachment_179851" align="alignleft" width="500"]Warner Bros. Warner Bros.[/caption]