But it was also far from perfect, losing control in a final reel awash in cartoon violence.
Its sequel unfortunately picks up where the first left off - with the nastiness but little of the intelligence. The first was borderline interesting; this is just vacuous.
It is again inspired by the work of the Scottish comic book writer Mark Millar, but director and co-writer Matthew Vaughn, a polished and canny filmmaker, has been replaced by newcomer Jeff Wadlow, and the lack of experience is glaring.
With the death of her father, the masked vigilante Big Daddy, the aforementioned, purple-wigged ninja-styled Hit Girl (Chloë Grace Moretz), real name Mindy, is going it alone as a solo super-heroine. Now 15, she allows her guardian to drive her to school each day, before skipping class and hitting the streets. Her friend Dave, aka Kick-Ass (Aaron Taylor-Johnson), implores her to team up. Much as her father once taught her, she now trains Dave to be something more than a well-meaning geek in a green wetsuit.
Their previous exploits have encouraged a wave of amateur superheroes, who have grouped together as The Justice League, under the leadership of Colonel Stars and Stripes (Jim Carrey). Dave enthusiastically joins their number, just as Mindy is prompted to review her life, hang up her weapons and attempt life as an ordinary schoolgirl. Both ventures go awry.
One value of Millar's proposition is that it casts light on the fact that the "heroes" in all comic-book adventures are, effectively, vigilantes (something only Batman, of the classic superheroes, really alludes to), and so themselves are outside the law. And in many of these stories the heroes cause as many problems as the so-called villains.
Both these themes are paid lip service here, but the script is simply too lame to carry them with any effect. Having characters simply bang on about "the real world" doesn't work as valid commentary. For much of the time it feels as though we're watching a high-school sitcom, albeit one peppered with slice-and-dice hostility. Most of the characters are either mad, bad or seriously delusional.
There are a few true moments provided by the two leads, for example when Mindy, this tough, no-nonsense young fighter, realises that kids can be just as hurtful as crooks, or the desperately naïve Dave learns of the very real consequences of his fantasy heroism.
But their scenes are too frequently interspersed with those featuring the indescribably irritating Christopher Mintz-Plasse as the crazed rich kid from the earlier film, Red Mist, who has rebranded himself with an unprintable name and hired a band of psychopaths to tear up the city. It's a destructive performance, for all the wrong reasons.
The clearest indication of the failure of the film is the innocuous turn by Jim Carrey, the most live-wire and imaginative of performers, who is virtually unrecognisable as the dull Colonel. As the most accomplished star in the line-up, Carrey has a big act to follow, namely Nicolas's Cage's typically fruity and discomforting turn as Big Daddy. He can't compete.