One day, mild-mannered high school comic book fan Dave Lizewski (Aaron Johnson) decides to become a superhero... even though he has no superpowers or training. But the legend of 'Kick-Ass' soon catches on, inspiring copycat vigilantes like Damon Macready (Nicolas Cage) and his deceptively sweet little girl Mindy (Chloe Moretz) while capturing the unwanted attentions of the city's most fearsome crimelord (Mark Strong). Hard-wiring audacious action to a savagely funny script, Kick-Ass makes Crank look positively undercharged.
With the 'gritty realism' of Watchmen and The Dark Knight elevating the capes and tights flick beyond the geek demographic, you'd think that a return to - and celebration of - day-glo costumed crime fighting would be a disaster.
But Kick-Ass is a comic book debut that's so bold, confident and creatively super-powered that it leaves Zack Snyder and Christopher Nolan's award-winning peers in its wake.
It's the post-modern kick in the nuts to the credibility-clamouring seriousness that the genre had spent so many years striving for, and positions Kick-Ass as this year's Zombieland: hilarious, irreverent and wish-fulfillingly electrifying.
Dave Lizewski is the modern everyman that Peter Parker so wants to be. Not too nerdy, but definitely not part of the 'cool' gang, most of his time is spent drifting to and from high school and the local comic store with his equally mundane friends.
That is, until he sits up and questions exactly why it is that no-one's ever properly tried to be a real life superhero. Donning a mail-order customised wetsuit and budget truncheon, 'Kick-Ass' heads out onto the streets... and immediately receives a vicious beating.
Yet second time around, armed with only 'good intentions and a slightly elevated capacity to take a kicking' (courtesy of the prior assault's nerve-numbing damage), he finds his YouTube-captured actions have sparked a wave of copycats - including a deadly, deranged father-and-daughter duo (Cage and Moretz), and a possible sidekick (Superbad's McLovin, Christopher Mintz-Plasse) - and drawn the psychotic attention of the city's major crime boss, Frank D'Amico (Strong).
Johnson seems far better suited to this fun escapism than Nowhere Boy, Mintz-Plasse throws in a suitably wimp-tastic performance as Red Mist, and Cage finally seems to have found a tone that accommodates his ridiculous over-acting (his 'Adam West' crimefighting voice is hilariously spot-on).
But make no mistake, the name on everyone's lips will be Hit-Girl.
Moretz will have audiences simultaneously cheering and speed-dialling the NSPCC after her outlandish, terrifying and jaw-dropping performance as the pint-sized assassin. Whether slicing bad guys in half with samurai swords or cheerfully, innocently playing around with her father, she's the embodiment of Kick-Ass' impressive tonal contradictions.
Simultaneously hyper-comic and yet believably grounded (the reason why Batman isn't a credible 'real world' superhero - "because he had all that imaginary expensive s**"), Vaughan and his cast have created a universe that sucks you in and doesn't let go.
Peppered with zeigeisty one-liners, adrenalised action set-pieces (including a breathtaking strobe light take-down that'll stay with you long after the movie ends), and a hilarious script that balances the superhero, teen comedy and action genres with confidence, Kick-Ass is likely the most unashamedly enjoyable film you'll see this year.
Considering Vaughan single-handedly funded the project when every major studio he approached ran away screaming, it's fitting that Kick-Ass' self-propelling mission statement is the hilariously anti-Spidey 'With no power comes no responsibility'.
And, damn, if it isn't fun.