CLIPS on Instagram: " Fun fact: The Dark Knight (2008) Heath Ledger kept a “Joker diary” while preparing for his role in The Dark Knight .He locked himself away in a hotel room for about six weeks to get into character. The diary was filled with disturbing notes, drawings, and ideas about the Joker’s mindset, including lines like “enjoy the little things” and references to A Clockwork Orange. It helped him fully embody the chaotic and unpredictable nature of the character."