Heath Ledger
The late Heath Ledger's picture is displayed after he wins the Oscar for best supporting actor for his role in "The Dark Knight" during the 81st Academy Awards in Hollywood, California February 22, 2009. Reuters/Gary Hershorn

In 2009, Heath Ledger won the Academy Award for Best Actor in a Supporting Role for his portrayal of the Joker in “Batman: The Dark Knight.” On screen, his acting was beautiful, albeit menacing, but reports are now proving just how deep the late actor immersed himself in the role.

According to a report by Page Six, police authorities who investigated Ledger’s residence in New York walked into a loft filled with “Batman” paraphernalia -- comic books and other pieces of literature on the Joker and clowns, various clown figurines, as well as recordings of Ledger practicing his voice for his portrayal of the Joker. Evidently, the late actor completely immersed himself in the world of the Clown Prince of Crime.

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A source of the publication confirmed that Ledger was studying the origin of clowns and the performances of his predecessors, including Jack Nicholson’s. Oddly enough, Nicholson admitted to a photographer in London that he had warned Ledger of the darkness that would follow him after playing the Joker.

And while Ledger's apartment was full of different books, trinkets and research, detectives noted how “immaculately clean” the area was. “He was a perfectionist who clearly had a lot of respect for the character,” the source said. “All of that stuff was very tidy. He cared a lot about it.”

In 2008, Ledger was pronounced dead at the age of 28. A New York City medical examiner’s report officially reasoned his death to an “acute intoxication by the combined effects of oxycodone, hydrocodone, diazepam, temazepam, alprazolam and doxylamine.” In other words, it was an accidental drug overdose from an abuse of prescription pills. He was found dead on Jan. 22, 2008, by a masseuse who had arrived at the loft for a scheduled appointment.

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Following his death, a documentary was released entitled “Too Young To Die,” which focused on Ledger and his journey in filming “Batman: The Dark Knight.” The film disclosed an eerie journal that the actor kept with “The Joker” written on the front. Inside were various photos, comic strips and drawings of the popular villain, other clowns and even hyenas. On the back of one of the pages, Ledger had ominously scribbled “bye bye.”

Watch "Batman: The Dark Knight" trailer