Handsome actor Heath Ledger died a tragic and untimely death when he overdosed on drugs during the filming of The Dark Knight. Ledger had been suffering from depression, anxiety, and, as a result of the two, sleep deprivation. There is speculation over whether his death was suicidal or accidental, but most see it as a tragic accident. Ledger’s problems were apparently exacerbated by his stressful role as evil villain The Joker. Former Joker Jack Nicholson even said he warned Ledger, but later claimed it was in regards to taking the drug Ambien. Ledger himself, however, admitted that the role was ‘physically and emotionally draining’, leaving him unable to sleep but a measly two hours per night.