The Real Reason Heath Ledger Licked His Lips So Much In The Dark Knight

Heath Ledger is famous for his dedicated portrayals of a wide range of characters, from the closeted gay cowboy Ennis Del Mar in "Brokeback Mountain" to the high school heartthrob Patrick Verona in "10 Things I Hate About You." However, Ledger's most iconic role was undoubtedly his performance as the Joker in the 2008 movie "The Dark Knight," thanks to his fresh take on the classic Batman supervillain. 

His Joker is easily the most memorable character in the film, surely contributing to the incredible staying power of the movie, which remains popular to this day. According to Box Office Mojo, "The Dark Knight" would gross over $1 billion worldwide, although Ledger himself would not see it reach its immense success, as he tragically died in January 2008 from an accidental drug overdose, several months before its release.

Heath Ledger's Joker is full of idiosyncrasies — the twitching, the grumbling yet shrill voice, the very intentional blinking — idiosyncrasies which the actor kept track of in a diary dedicated to his Joker persona. But perhaps the most distinct characteristic of Ledger's Joker is his incessant lip-licking, which the actor uses almost as punctuation, finishing many of his twisted remarks with a swift smack of the lips or by gliding his tongue over the corners of his mouth. 

This defining feature of Ledger's Joker is more than just a random tick that the actor decided would complement the character, though, and the real reason for it may surprise you.

Heath Ledger's Joker was different from past actors' interpretations of the character thanks to his unique acting capabilities and distinct perspective on the role, but that doesn't mean that he did not have some help finding his approach to the character along the way. Fans have noted the similarities between Ledger's Joker and the real-life behavior of American singer-songwriter Tom Waits, and he also worked with dialect coach Gerry Grennell to achieve the specific voice that would ultimately become so integral to the character. 

Grennell and Ledger had met sometime in 2000 or 2001, when they were both shooting movies in Prague (Grennell was working as a dialect coach on the movie "From Hell," while Ledger was filming "A Knight's Tale" — via Today with Maura and Daithi). Several years later, Grennell and Ledger teamed up to create the iconic Joker voice.

Grennell is also important to the story of Ledger's Joker because of a revelation he made in the 2017 documentary "I Am Heath Ledger," about the actor's career, life, and death. In an interview for the documentary, Grennell revealed that the Joker's lip-licking was actually a very practical response to an inconvenience caused by special effects makeup — in this case, the scars on either side of the Joker's mouth: "The prosthetics came up onto the lip, and feathered onto the lip, so it was almost halfway into the mouth. And, of course, when you speak, the feathering of the prosthetics became loosened. The last thing Heath wanted to do was to go back and spend another 20 minutes or half an hour trying to get the lips glued back again. So he licked his lips — a lot. And then slowly that became part of the character." Talk about serendipity!

It's amazing how something so uninteresting as glue not adhering well to the parts of the face where there's a lot of movement became such a key feature of Heath Ledger's portrayal of the Joker. And the breaking of this news definitely caught some fans off guard. Upon realizing the real reason for Heath Ledger's characteristic lip-licking as the Joker, fans of "The Dark Knight" took to Reddit to discuss — and have a little fun.

Some doubled-down on their theories about why Ledger licked his lips so much, like one fan who wrote, "I thought it was because antipsychotic medications cause tardive dyskinesia," a nervous system condition that can appear as twitches, blinking, and darting of the tongue. But most took the news with amusement. The comment section is full of paraphrases of iconic Joker lines, now altered to reflect the reality of the finicky scar prosthetics: "You wanna know how I got these scars... put on?", "Do you wanna know how I keep these scars in place?"

One of the best is a comment from user CardinalNYC, which reads, "My father was... a costume designer... and a fiend." A hilarious comment thread continued from there, paraphrasing the Joker's entire speech with increasingly ridiculous substitutions.

"The Dark Knight" will go down in history for its expert acting, incredible characterization, and world-class costume design and makeup, and it will now never be forgotten that those attributes all collided in the unlikely place that is the distinctive lip-licking habit of Heath Ledger's Joker.