In honor of the anniversary, here's an in-depth look at the actor's portrayal of the Joker
10 Best Heath Ledger Movies: Remembering His Most Memorable Movie Roles
The Dark Knight Turns 15: How Heath Ledger Was Remembered (Flashback)
The Dark Knight Turns 10: Remembering Heath Ledger's Iconic Role
Heath Ledger - WTF Happened To.?! (podcast)
Why is Heath Ledger's Joker so loved by the people? Are there any actors who can play him better than him? - Quora
Remembering the life and career of Heath Ledger – New York Daily News
Ledger sought out challenging roles – East Bay Times
Is the Dark Knight only considered a good film due to Heath Ledger's performance as the Joker? If he had not played the Joker, would the film still be considered good? Or
Prime1Studio x Blitzway The Joker 1/3 Scale Figure
Opinion: Why The Dark Knight Is Still the Best Superhero Movie Ever - IGN
Diablo gets the first look at The Dark Knight, Popcorn Picks