Warner Bros. 2019. Drama. 122 minutes.

The Joker would seem like catnip for any actor willing to throw himself down the rabbit hole because, as far as movie audiences are concerned, he only has one defining characteristic: he’s nuts. It’s a pretty large playground to frolic in filled with opportunities for an actor to let their id run free. Jack Nicholson’s take was more in line with Cesar Romero’s campy and cackling TV version, which, given that it was for director Tim Burton, seemed darkly comical at the time. Now it’s just comical in a ridiculous way that’s hard to take seriously.

Heath Ledger, by dint of playing the role in a Christopher Nolan film, made the character a weaponized Nihilist, the worst-case scenario of a Seattle grunge wastrel who went insane after watching too many post-apocalyptic movies with his bedroom door closed while sniffing glue. The performance blew our doors off; the fidgety demeanor, the darting eyes and the way his tongue would fly around his mouth as if licking his lips for another chance to remind us that the world will end in fire. It permanently readjusted our expectation of what character could be. It seemed destined to become, in these troubled and confusing times, the definitive reading of the character and maybe it still is. But in director Todd Phillips’ relentlessly grim, stand alone film, Joker, Joaquin Phoenix does something not even Ledger could do and it’s startling to watch: he takes all the joy and humor out of the Joker. This Joker is not campy nor is he cool. He is a black hole of psychological damage and dangerous instability. Ledger made it safe for the Joker to not be funny. Phillips and Phoenix, as much as can be hoped for when a big studio crosses its fingers and messes with valuable IP, has done something even more surprising: they made him truly sick.

In this telling, of course, Arthur Fleck is Travis Bickle. Martin Scorsese’s Taxi Driver is the touchstone for Phillips, something he has admitted, and while that might be one reason to dismiss the film outright it’s actually a major reason the film works. Its debt to the Scorsese classic is evident but Joker creates its own world of dank, hopeless urban alienation and tells its own tale of class-based chaos and its newfound champion. It visually traffics in yesterday but its concerns feel like today, if not right this second. Mark Friedberg’s production design is both a nightmare vision and realistic depiction of urban decay. The grit, the heat and the “super rats” of a big city in decline becomes the fetid, barren soil from which Arthur, already a mentally unstable collection of inappropriate responses and anti-social behavior, can grow.  What allows him to become Joker is not one defining event that pushes him off a cliff but rather a succession of indignities that nudge him ever so slowly into the abyss. And it begins in the first few minutes as Arthur, sign-spinning on the street in his inglorious job as a rent-a-clown, gets roughed up by some punks. In these early moments, the sad clown laying prone in an alley after a serious beatdown, we actually feel sorry for him. “I just don’t want to feel so bad any more,” he says to a city-employed shrink, someone who barely cares about him and doesn’t (in Arthur’s view) even listen to him. And when city cutbacks takes this key lifeline away from him, it’s representative of a system that, to society’s detriment, doesn’t care about its mentally ill. After that, there’s precious little left to keep Arthur from sinking right to the bottom and becoming a full-blown nut-job.

Arthur’s only remaining tether to reality is his odd but loving relationship with his mother, Penny (Francis Conroy). A sickly and weird bird who one can imagine being the mother of a future psychopath, Penny spends most of her day watching television. Often she’s waiting for a new TV interview featuring her former boss Thomas Wayne. Penny holds out the pathetic hope this soon-to-be Gotham City mayoral candidate will help Penny and Arthur out of their dire financial straits. Mostly though, bonkers mom and her screw-loose son enjoy watching Live with Murray Franklin, a late night talk show whose eponymous host Arthur fantasizes about as being the father he never had.

As a notoriously bad talk show guest in real life, Robert De Niro may seem like a risky choice to play a late night host. But the casting is clever for obvious reasons: De Niro was not only the title Taxi Driver but he was also deranged fan, Rupert Pupkin, who’ll do anything for a spot on the late night talk show hosted by Jerry Lewis in Scorsese’s 1983 The King of Comedy. De Niro, who has almost completely destroyed his legacy with his long running series of lousy choices (Rocky and Bullwinkle, anyone?), is perfectly cast here even if he’ll never make anyone forget Johnny Carson.

Co-writers Phillips and Scott Silver make a wise choice from the get-go: Joker is strictly a character piece. He’s not planning a bank robbery nor is he trying to defeat the hero. He has no goal. This is the story of one man’s descent into madness on a rocket that reaches escape velocity when Arthur, on the subway and carrying a pistol given to him by a colleague, guns down three Wall Street douchebags who were taunting him. This triple murder introduces a class warfare layer to the film, as newspaper headlines blare, “Kill the Rich: A New Movement?” and Arthur begins to see a part for himself in the growing citywide discontent. This is where Todd Phillips (the Hangover films, may we remind you) shows a surprising level of maturity as a writer and a director. That Joker would become a symbol of the riotous discontent of the working man against the ruling elite might seem “so very now” but its class warfare component really isn’t a political statement: it’s the ultimate extension of what Arthur Fleck always wanted but, in a world that on a good day merely ignores him, failed to achieve: to be noticed (cue the wackadoodle “incel” comparisons).

As we learn more about Arthur’s upbringing, one that teasingly introduces a connection to the Wayne family, there are those who will argue that Arthur is ultimately just another product of a bad childhood and how boring is that? But don’t mistake that as taking the easy way out. Phillips finds avenues to explore that make the cliché feel part of a deep dive into the elements that might turn such a kid into a raving, murderous sociopath. As a study of man’s psychotic meltdown, Joker is way more interesting than other more sober-minded takes on the subject and not just because a DC comic film isn’t beholden to reality.

But it all comes down to Phoenix. The 3-time (about to be 4-time) Oscar nominee is all-in, losing enough weight to reveal his ribs and angular shoulder blades. His cackle comes from so far deep in his belly that it’s indistinguishable from a cry. It’s a laugh less cartoonishly maniacal than it is a shriek from his soul, an ear-splitting screech so unexpected that when it erupts he hands those around him a laminated card explaining that he has a condition that causes him to laugh uncontrollably.  Phoenix show us what happens when a lifetime of disappointments, held in check by seven medications, is finally unleashed, a wound with the scab ripped off and ready to spread like flesh-eating bacteria. When he emerges, fully formed, in his brick red sportcoat, orange vest and green shirt (that outfit alone will earn costume designer Mark Bridges an Oscar nomination), he is not just one of pop culture’s great villains emerging newly reconsidered by one of America’s great actors. At that moment, the one where Arthur Fleck becomes a howling, murderous walking personification of loneliness and mental illness gone nuclear, he is truly dressed for success.