First, some context: I have always been a strong advocate of the belief that one of the reasons The Joker - Batman's arch-nemesis - works so well as a villain, and has endured so long in comics, is because he doesn't have (and doesn't need) a definitive origin story.
As the ultimate unreliable narrator, he's had numerous possible origin stories since he first appeared in 1940, but we've never learned who he actually was as none of these possible backstories have ever stuck.
Part of my issue with prequels is that they very rarely truly complement the original material: Jedi knights were much cooler without midichlorians, xenomorphs were scarier before we knew who "engineered" them etc
However, taking all that into account, writer/director Todd Phillips' Joker is an incredibly powerful and engaging movie.
It's hard to believe that the same person responsible for the odious Hangover movies could craft this amazing Scorsese homage, a Taxi Driver for the comic book movie generation.
Set in 1970s Gotham, the rundown city is a roiling powder keg of social inequality, ready to blow at any moment.
Mentally unbalanced, clown-for-hire and would-be stand-up comedian Arthur Fleck (Joaquin Phoenix) lives with his frail mother (Frances Conroy) and suffers a serious of brutal beat-downs - both physical and emotional - that push him over the edge.
However, media coverage of his violent actions are the spark that ignites the city, and as society explodes around him, Arthur is shocked to find himself on course to meet his idol: TV chat show host Murray Franklin (Robert De Niro).
As well as a Joker origin story, the movie also stands as a Batman origin story, as Thomas Wayne (Brett Cullen) and even young Bruce (Dante Pereira-Olson) get drawn into Arthur's story.
A gritty take on the world of the Batman comics - following in the footsteps of Christopher Nolan's Batman trilogy - Joker is Taxi Driver meets King Of Comedy, with a sprinkling of Fight Club and Frank Miller's The Dark Knight Returns comic book run.
Fleck is Travis Bickle, equally awkward with women and full of pent-up aggression, but with his professional clowning substituting for Bickle's late-night cab driving, both giving them - they believe - insight into society's ills.
Echoing De Niro's riveting Oscar-nominated performance in Taxi Driver, Joaquin Phoenix owns Joker with his magnetic, and tragic, performance as the delusional Fleck, trying to find purpose in his life and an explanation for why all this shit keeps happening to him.
He brings a catalogue of tics and quirks to the character that make his Joker as shockingly memorable as that of the late Heath Ledger.
Are we supposed to feel sympathy, or even empathy, for Arthur? Or simply understand what drove him to do what he did? Or believes he did, if he really did it!
For all we know, at the end of the day, Arthur is just a Joker, but not the Joker!
A surprisingly cerebral and layered story, Joker (available from today on Sky Cinema) definitely demands multiple viewings to simply pick apart which elements - beyond the ones that are flagged up - are real and which occur only in Arthur's head.
Psychologically disturbing viewing, the 122-minute movie exquisitely encapsulates the Alan Moore quote from the highly regarded Batman/Joker graphic novel The Killing Joke:
"All it takes is one bad day to reduce the sanest man alive to lunacy. That's how far the world is from where I am. Just one bad day."While I wouldn't want all comic book movies to follow Joker's lead, this is an excellent demonstration of how the Marvel method isn't the only way to make to make outstanding movies in this genre.