On The Dark Knight's 10th anniversary, a look back at Heath Ledger's unforgettable Joker is the pop culture retrospective we deserve and certainly the one we need right now.

Two thirty-something, crime-fighting billionaires with a superhero complex — who possess no super-powers whatsoever but merely some fancy armour, helmets and futuristic gadgets — featured in two important films in 2008 that would change the landscape of Hollywood forever. Each provided its own unique blueprint for the future of a genre that has now come to rule the global box office.

The superhero movie genre has certainly hit its stride over the last decade, thanks in large part to Iron Man and The Dark Knight.

While plenty has already been written about how Iron Man became the face of a movie empire (and a cinematic universe that continues to expand and shows no signs of winding down anytime soon), a look back at The Dark Knight is the pop culture retrospective we deserve and certainly the one we need right now on its tenth anniversary.

Christopher Nolan's sequel to Batman Begins, starring Christian Bale as the titular superhero, remains the gold standard of superhero films to this day. Considering we must have had more than a couple dozen films — based on Marvel and DC Comics alone — since its release, it must mean the British filmmaker got a lot of things pitch-perfect. From the outset, fans — DC or otherwise — have raved and gushed about the film. It also received near universal acclaim from critics with many praising its plot, pacing, characterisation, suspense, music and cinematography. It transcended a genre that is still trivialised, because it isn't considered "serious film-making", by earning eight Oscar nominations and winning two. It certainly broke new ground in the comic book genre.

However, the chief reason for all this decade-long bouquet throwing for The Dark Knight is an anarchy-loving, maniacal nihilist played by the late Heath Ledger. To put it simply, he's the reason the film works.

Batman's adversaries have often been more fascinating than Batman himself in the comics because it often felt like Bruce Wayne was merely confronting his own Jungian shadow-self, full of Id's impulses. And no adversary knew how to push Batman's buttons better than the Joker.

Ledger's rendition of the Joker — complete with blood-red lips, dark-shadowed eyes and an elongated grin that literally cuts into his face in jagged scars — is equal parts terrifying and awe-inspiring. He is a cheerfully homicidal, criminally ingenious and a psychologically complex tour de force. From the tone-setting bank robbery scene in the prologue until his capture, dangling upside-down from a high-rise building, he truly lives up to his self-given moniker — "The Agent of Chaos."

Much like in the comics, Ledger's Joker taunts Batman by using the caped hero's moral code (Thou Shalt Not Kill) against him.

"You truly are incorruptible, aren't you? You won't kill me out of some misplaced sense of self-righteousness and I won't kill you because you're just too much fun. I think you and I are destined to do this forever." - The Joker in The Dark Knight

So, he forces the Bat, Harvey Dent and the common folk of Gotham City to reveal their true nature. He believes that deep down we are all as wicked and villainous as he is and there's a monster lurking inside all of us waiting to be unleashed.

He proves this by orchestrating events which turn the conflicted but well-meaning District Attorney of Gotham City into a sadistic psychopath whose every decision is determined by the flip of a coin. Then, he pitches his own twisted version of the Prisoner's Dilemma or what he calls a "social experiment." He rigs two boats — one full of convicted “Harvey Dent’s most wanted scumbag collection” and the other full of innocent civilians — with explosives and presents them with an ultimatum: The two ships have until midnight to press a detonator that will destroy the other before the Joker blows up both of them himself. The Joker simply wants to make a comment on human nature, anticipating the civilians to detonate the bomb on the convict-filled ship.

This manic take on the quintessential Batman villain is what made Ledger's performance unforgettable. In order to prepare for the role, the actor took inspiration from another charming sociopath and anarchic warrior with an "ultraviolent" obsession — Alex in Anthony Burgess’ A Clockwork Orange.

"I sat around in a hotel room in London for about a month, locked myself away, formed a little diary and experimented with voices — it was important to try to find a somewhat iconic voice and laugh. I ended up landing more in the realm of a psychopath — someone with very little to no conscience towards his acts." - Heath Ledgers explains the process behind his transformation in an interview with Empire magazine

There's no doubt it worked as he not only redefined one of the most iconic comic book villains, he also single-handedly elevated the film above its missteps. And yes, there are a few. While it is compelling to watch the Joker's orchestrated corruption of Harvey Dent, the introduction of a second villain shouldn't have come at the cost of Ledger's character. His performance was what made the movie engaging and the Joker's exclusion from the film's third act for what — hardly eight minutes of screen time for Two Face before he is killed abruptly — seemed unnecessary. It could have easily been explored in a subsequent film.

At times, the film has more moving parts than an orchestra, only they don't always work in harmony. In his efforts to make a superhero film that takes its ideas seriously, Nolan tries to explore more issues than he can handle — from the post–9/11 invasive surveillance technology plot point to order vs chaos and other Nietzschean themes.

It may be an unpopular opinion but Batman Begins is actually a more definitive Batman film in Nolan's trilogy. It's an origin story that is closer to the comics (Batman: Year One) and one that allows us a deeper look into the psyche of the Bat. With The Dark Knight, Nolan is not sure if he wants to explore Bruce Wayne's arc, Harvey's or the Joker's and instead ends up half-assing all of them. As Ron Swanson says in Parks and Recreation, "Never half-ass two things. Whole-ass one thing."

Regardless, The Dark Knight remains a landmark moment in the genre and proves it is complex villains that make compelling superhero films. This lesson, however, seems to have got lost along with many others with regards to DC and Marvel's filmmakers, who have both continutally persisted with one-dimensional villains who wreak CGI-saturated chaos for no apparent reason. At least, Marvel has started to understand the value of well-written villains, with this year's Erik Killmonger in Black Panther and Thanos in Avengers: Infinity War easily being MCU's most fascinating villains since the delinquent trickster Loki in The Avengers.

Marvel's Iron Man laid the first stone of a shared narrative continuity that skilfully combined huge action set pieces with emotionally-charged character development and some light-hearted humour. Meanwhile, The Dark Knight has left a legacy of dark hues, cheerless tone, humourless plots, stoic superheroes and Batman's bone-rattling, bass heavy guttural voice for the Nolan wannabes (Read: Zack Snyder) of DC Entertainment.

Nolan and Ledger combined to create a cinematic rendition that masterfully paid homage to some of the most iconic comics in the Batman universe. DC's films — bar Wonder Woman — are sadly not what their legacy deserves or their fans need.