More than seven years after the unexpected death of his son, Heath Ledger's father, Kim Ledger, is giving fans a rare glimpse into the actor's mind just before his passing. Heath, 28, was found dead in his New York City apartment in January 2008, shortly after wrapping production on "The Dark Knight Rises." At the time, it appeared he had committed suicide. His death was later ruled an accidental overdose.

Clips from the German docuseries "Too Young to Die" show Kim flipping though the pages of a diary his son had kept while playing the role, revealing just how dark his life had gotten during filming. According to Complex, a majority of the diary was filled with comic book clippings, playing cards, photos of clowns and stills from the film "A Clockwork Orange," though there was the occasional message scrawled across a page or two.

While going through the journal Kim noted that it was normal of his son to immerse himself completely in a role. He did, however, acknowledge that "The Dark Knight Rises" was "a whole new level" for him. As chilling as the images in Heath's joker diary were it's his final message that we think viewers will find truly haunting. 

“At the end of shooting, he wrote goodbye on the back of the last page,” Kim said. “It was hard to read that.”

In the years since Heath’s death, his family has gone the extra mile to ensure that they are able to keep his memory alive. As previously reported, his sister, Kate Ledger, told the Sunday Telegraph that she makes sure to tell his daughter Matilda Rose, 9, about him often. At the time, she said that she believes Matilda knowing things about her father will help her as she learns and grows without him physically by her side. Kate told the publication she thought it was “so important” for her to know where she came from in order to fully know herself as she gets older. She also praised her mother, actress Michelle Williams, for raising her on her own.

“Michelle really does keep things ‘real’ for her,” she said. “And her existence, although different from most, is as normal as possible in an abnormal world.”

Check out the clip from “Too Young to Die” below: